View source for 1 Line (Sound Transit)

{{short description|Light rail line serving Seattle, Washington}}
{{redirect|Central Link|other uses |Central link (disambiguation){{!}}Central link}}
{{featured article}}
{{Use American English|date=June 2023}}
{{Use mdy dates|date=January 2024}}
{{Infobox rail line
| box_width                       = 
| name                            = 1 Line
| color                           = {{rcr|Sound Transit|Line 1}}
| logo                            = Line 1 (Sound Transit) icon.svg
| logo_width                      = 35px
| logo_alt                        = Link light rail logo
| image                           = Link LRV 128 approaching Sea-Tac Airport Station.jpg
| image_width                     = 300px
| image_alt                       = A train with four cars, traveling over a concrete bridge under catenary wires.
| caption                         = A four-car Series&nbsp;1 train on the 1&nbsp;Line approaching [[SeaTac/Airport station]]
| other_name                      = {{plainlist|
* Central Link
* Red Line
}}
| type                            = [[Light rail]]
| system                          = [[Link light rail]]
| status                          = <!-- Only to be used when line is non-operational -->
| locale                          = [[Seattle]], Washington, U.S.
| start                           = [[Lynnwood Transit Center|Lynnwood City Center]] (north)
| end                             = [[Angle Lake station|Angle Lake]] (south)
| stations                        = 23
| daily_ridership                 = 78,944 (2023, weekdays)<ref name="Ridership"/>
| ridership2                      = 
| website                         = {{URL|https://www.soundtransit.org/schedules/link-light-rail|soundtransit.org}}
| open                            = {{Start date|2009|07|18}}
| owner                           = [[Sound Transit]]
| operator                        = [[King County Metro]]
| character                       = At grade, elevated, and underground
| depot                           = 
| stock                           = {{plainlist|
* 62 [[Kinki Sharyo|Kinkisharyo-Mitsui]] LRVs
* 152 [[Siemens S700 and S70|Siemens S700]]s
}}
| linelength_mi                   = 33.15
| tracks                          = 2
| gauge                           = {{Track gauge|ussg|allk=on}}
| electrification                 = {{1,500 V DC|conductor=overhead}}
| speed_mph                       = 55
| map                             = {{Central Link map|inline=1}}
| map_state                       = collapsed
}}

The '''1{{nbsp}}Line''', formerly '''Central Link''', is a [[light rail]] line in [[Seattle]], Washington, United States, and part of [[Sound Transit]]'s [[Link light rail]] system. It serves 23 stations in [[King County, Washington|King]] and [[Snohomish County, Washington|Snohomish]] counties, traveling {{convert|33|mi|km|0}} between {{stl|Sound Transit|Lynnwood City Center}} and {{stn|Angle Lake}} stations. The line connects [[Lynnwood, Washington|Lynnwood]], [[Mountlake Terrace, Washington|Mountlake Terrace]], [[Shoreline, Washington|Shoreline]], the [[University District, Seattle|University District]], [[Downtown Seattle]], the [[Rainier Valley, Seattle|Rainier Valley]], and [[Seattle–Tacoma International Airport]]. The 1{{nbsp}}Line carried over 26&nbsp;million total passengers in 2023, with an average of nearly 80,000 daily passengers on weekdays. It runs for 20 hours per day on weekdays and Saturdays, with [[headway]]s as low as six minutes during [[peak hour]]s, and reduced 18-hour service on Sundays and holidays.

Trains are composed of three or more cars that each can carry 194 passengers, including 74 in seats, along with wheelchairs and bicycles. Fares are calculated based on distance traveled and are paid through the regional [[ORCA card]], paper tickets, or a mobile app. Sound Transit uses [[proof-of-payment]] to verify passenger fares, employing fare ambassadors and [[transit police]] to conduct random inspections. All stations have [[ticket vending machine]]s, [[public art]], bicycle parking, and bus connections, while several also have [[park-and-ride]] lots.

Voters approved Central Link in a 1996 ballot measure and construction began in 2003, after the project was reorganized under a new budget and truncated route in response to higher than expected costs. The light rail line, which followed decades of failed transit plans for the Seattle region, opened on July 18, 2009, terminating at {{stn|Westlake||Sound Transit}} in the [[Downtown Seattle Transit Tunnel]] and {{stn|Tukwila International Boulevard}} near Sea–Tac Airport. It was extended south to {{stn|SeaTac/Airport}} in December 2009, north to the University of Washington in March 2016, and south to Angle Lake in September 2016. The line was temporarily renamed the Red Line until its designation was changed to the 1{{nbsp}}Line in 2021, coinciding with an extension to Northgate.

The first cross-county extension, north to Lynnwood, opened in August 2024. A further southern extension to [[Federal Way Downtown station|Federal Way]] is planned to open in 2026. The [[2 Line (Sound Transit)|2&nbsp;Line]], planned to connect Seattle to the [[Eastside (King County, Washington)|Eastside]] suburbs, will form a multi-line network via its connection with the 1{{nbsp}}Line in 2025. Further expansion under [[Sound Transit 3]] will divide the current corridor between two lines, the 1{{nbsp}}Line from [[Ballard, Seattle|Ballard]] to [[Tacoma, Washington|Tacoma]] and the [[3 Line (Sound Transit)|3&nbsp;Line]] from [[Everett, Washington|Everett]] to [[West Seattle, Seattle|West Seattle]].

==History==
{{main|History of Link light rail}}

===Background and early transit proposals===
[[File:Seattle-Tacoma interurban railway, circa 1920s (17157602651).jpg|alt=A train with two cars passing through a built-up downtown on tracks embedded in the street|right|thumb|A Tacoma-bound [[Puget Sound Electric Railway]] [[interurban]] train seen in the 1920s]]

Public transit service within Seattle began in 1884, with the introduction of the city's first horse-drawn [[streetcar]] line. The system had been replaced with a network of electric streetcars and [[Cable car (railway)|cable cars]] by the end of the decade, which spurred the development of new [[streetcar suburbs]] across modern-day Seattle.<ref>{{cite news |date=February 1, 1987 |title=A look into rail's past |page=B3 |work=[[The Seattle Times]]}}</ref><ref name="HL-Streetcars">{{cite web |last=Crowley |first=Walt |author-link=Walt Crowley |date=October 2, 2000 |title=Street Railways in Seattle |url=http://www.historylink.org/File/2707 |url-status=live |archive-url=https://web.archive.org/web/20170918154346/http://www.historylink.org/File/2707 |archive-date=September 18, 2017 |access-date=September 17, 2017 |work=[[HistoryLink]]}}</ref> Interurban railways to [[Everett, Washington|Everett]], [[Tacoma, Washington|Tacoma]], and the [[Rainier Valley, Seattle|Rainier Valley]] were established after the turn of the century, giving the region an intercity passenger rail system to feed the streetcar lines.<ref>{{cite news |last=Dorpat |first=Paul |author-link=Paul Dorpat |date=November 6, 1983 |title=Plush as a Parlor: Some Interurban commuters paid more for a cushy ride |page=6 |work=The Seattle Times}}</ref> The interurban system failed to compete with the increasing popularity of automobile travel, capped by the completion of [[U.S. Route 99]] in the late 1920s, and was shut down.<ref>{{cite web |last=Crowley |first=Walt |date=September 19, 2000 |title=Interurban Rail Transit in King County and the Puget Sound Region |url=http://www.historylink.org/File/2667 |access-date=March 24, 2018 |work=HistoryLink}}</ref> By 1941, the streetcars had also been acquired by the municipal government and replaced with a [[Trolleybuses in Seattle|trolleybus network]].<ref name="HL-Streetcars"/><ref>{{cite news |date=December 10, 2007 |title=Seattle's streetcar history |page=A6 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20071210&slug=streetcartimeline10 |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154625/http://community.seattletimes.nwsource.com/archive/?date=20071210&slug=streetcartimeline10 |archive-date=September 18, 2017}}</ref>

Various proposals for a [[rapid transit]] system in Seattle, to replace the streetcar—and later bus—networks, were presented in the 20th century and rejected by city officials or voters due to their cost or other factors. In 1911, urban planner [[Virgil Bogue]] proposed a {{convert|41|mi|km|adj=mid}} system of subway tunnels and elevated railways as the centerpiece to a [[comprehensive plan]] for the city, which was rejected by voters.<ref>{{cite news |last=Sipe |first=Tyler |date=March 5, 2017 |title=Off track: Seattle rejects first mass transit ballot measure on March 5, 1912 |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/off-track-seattle-rejects-first-rapid-rail-network-measure-on-march-5-1912/ |url-status=live |url-access=limited |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110620/http://www.seattletimes.com/seattle-news/transportation/off-track-seattle-rejects-first-rapid-rail-network-measure-on-march-5-1912/ |archive-date=September 18, 2017}}</ref> The [[Seattle Center Monorail]], originally built for the [[Century 21 Exposition|1962 World's Fair]], has been the subject of several unsuccessful expansion proposals backed by Governor [[Albert Rosellini]] in the 1960s and Seattle voters in the early 2000s.<ref>{{cite news |last=Lindblom |first=Mike |date=July 30, 2002 |title=Another '60s revival: running a monorail along Interstate 5 |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20020730&slug=freewayrail30m0 |access-date=September 17, 2017}}</ref> The [[Forward Thrust]] Committee of the late 1960s proposed a {{convert|47|mi|km|adj=mid}} rapid transit system, to connect Downtown Seattle to [[Ballard, Seattle|Ballard]], the [[University District, Seattle|University District]], [[Lake City, Seattle|Lake City]], [[Capitol Hill, Seattle|Capitol Hill]], [[Bellevue, Washington|Bellevue]], and [[Renton, Washington|Renton]]. The federal government offered to fund two-thirds of the rail system's capital costs, approximately $770&nbsp;million (equivalent to ${{Format price|{{Inflation|US-GDP|770000000|1968}}}} in {{Inflation-year|US-GDP}} dollars),{{inflation-fn|US-GDP}} if $385&nbsp;million (equivalent to ${{Format price|{{Inflation|US-GDP|385000000|1968}}}} in {{Inflation-year|US-GDP}} dollars){{inflation-fn|US-GDP}} in local property taxes were approved by voters.<ref>{{cite news |last=Coffman |first=Larry |date=February 4, 1968 |title=Rapid Transit: Everyone Agrees It's Needed, but What Kind? |page=5 |work=The Seattle Times}}</ref> The rapid transit initiative was placed on the ballot in February 1968, but fell short of [[supermajority]] needed to pass. A second attempt in May 1970, with $440&nbsp;million (equivalent to ${{Format price|{{Inflation|US-GDP|440000000|1970}}}} in {{Inflation-year|US-GDP}} dollars){{inflation-fn|US-GDP}} in local funding and $870&nbsp;million (equivalent to ${{Format price|{{Inflation|US-GDP|870000000|1970}}}} in {{Inflation-year|US-GDP}} dollars){{inflation-fn|US-GDP}} in federal funding,<ref>{{cite news |date=May 17, 1970 |title=Tuesday Is 'Thrust' Day; The Biggest Issue: Rapid Transit |page=B1 |work=The Seattle Times}}</ref> failed amid a local economic downturn caused by layoffs at [[Boeing]].<ref>{{cite news |date=June 14, 1970 |title=Seattle Mass Transit Proposal Pleases Everybody but Voters |page=16 |work=[[The New York Times]] |url=https://www.nytimes.com/1970/06/14/archives/seattle-mass-transit-proposal-pleases-everybody-but-voters.html |url-status=live |access-date=February 12, 2018 |archive-url=https://web.archive.org/web/20180213142125/http://www.nytimes.com/1970/06/14/archives/seattle-mass-transit-proposal-pleases-everybody-but-voters.html |archive-date=February 13, 2018}}</ref> The federal funding earmarked towards the rapid transit system was granted to [[Atlanta, Georgia]], forming the initial funding for the [[Metropolitan Atlanta Rapid Transit Authority]]'s rail system.<ref>{{cite news |last=Cohen |first=Josh |date=October 14, 2016 |title=How Seattle blew its chance at a subway system |work=[[Crosscut.com]] |url=http://features.crosscut.com/seattle-forward-thrust-sound-transit |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170917000729/http://features.crosscut.com/seattle-forward-thrust-sound-transit |archive-date=September 17, 2017}}</ref>

===Light rail planning===

Following the failed Forward Thrust initiatives, [[Municipality of Metropolitan Seattle|Metro Transit]] was created in 1972 to oversee a countywide bus network, and plan for a future rail system.<ref>{{cite news |last=Lane |first=Bob |date=March 20, 1975 |title=Metro program looks to future |page=H7 |work=The Seattle Times}}</ref> In the early 1980s, Metro Transit and the [[Puget Sound Council of Governments]] (PSCOG) explored [[light rail]] and [[Bus rapid transit|busway]] concepts to serve the region,<ref>{{cite news |last=Lane |first=Bob |date=March 22, 1981 |title='Light rail' system might solve transit problems, says study |page=A16 |work=The Seattle Times}}</ref> ultimately choosing to build a [[Downtown Seattle Transit Tunnel|downtown transit tunnel]] that would be convertible from buses to light rail at a later date.<ref>{{cite news |last=Lane |first=Bob |date=April 22, 1988 |title=Metro makes tracks for tracks for future |page=B1 |work=The Seattle Times}}</ref> The PSCOG formally endorsed a light rail plan in 1986, recommending a system be built by 2020, and include a line between Seattle and [[Seattle–Tacoma International Airport|Sea-Tac Airport]],<ref>{{cite news |last1=Matassa Flores |first1=Michele |last2=Parrish |first2=W.Y. |last3=Shatzkin |first3=Kate |date=September 13, 1989 |title=Cities' influence takes off: Expanded roles with more clout for Sea-Tac and Federal Way |page=F1 |work=The Seattle Times}}</ref> with routing alternatives that served the Rainier Valley.<ref>{{cite news |last=Bergsman |first=Jerry |date=July 9, 1986 |title=Panel's advice: Plan now for rail |page=H1 |work=The Seattle Times}}</ref><ref>{{cite book |title=Central Link Light Rail Transit Project Final Environmental Impact Statement |date=October 22, 1999 |publisher=Sound Transit |page=G-36 |chapter=Appendix G: Environmental Justice Technical Report |oclc=42730086 |access-date=January 3, 2018 |chapter-url=https://books.google.com/books?id=TCQ3AQAAMAAJ&pg=RA1-PA36 |archive-url=https://web.archive.org/web/20180119063248/https://books.google.com/books?id=TCQ3AQAAMAAJ&lpg=RA1-PA36&ots=9P8ORpYdTo&pg=RA1-PA36 |archive-date=January 19, 2018 |url-status=live |via=Google Books}}</ref> A 1988 advisory measure on light rail planning was passed in [[King County, Washington|King County]], encouraging Metro Transit to accelerate the plan's timeline to open by 2000.<ref>{{cite news |last=Lane |first=Bob |date=November 9, 1988 |title=Ballot Issues: On track, voters say 'hop to' on rail transit |page=E9 |work=The Seattle Times}}</ref> In 1990, the [[Washington State Legislature|state legislature]] endorsed the creation of a regional transit board composed of politicians from King, [[Pierce County, Washington|Pierce]], and [[Snohomish County, Washington|Snohomish]] counties, with the goal of implementing the regional transit plan.<ref>{{cite news |last=Bergsman |first=Jerry |date=August 21, 1990 |title=Everett's OK may speed regional transit |page=C2 |work=The Seattle Times}}</ref> Several members of the [[Seattle City Council]] endorsed the rail plan on the condition that it pass through the Rainier Valley, by then an economically disadvantaged and majority-minority neighborhood.<ref>{{cite news |last=Kelleher |first=Susan |date=July 16, 2001 |title=Distorted facts led to Rainier rail route |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20010716&slug=rail16m |access-date=November 22, 2018}}</ref>

The Central Puget Sound Regional Transit Authority, later renamed [[Sound Transit]], was created in 1993 to write and present a regional transit plan for voter approval.<ref>{{cite news |last=Sachefer |first=David |date=July 7, 1993 |title=Regional transit unit gets go-ahead |page=B3 |work=The Seattle Times}}</ref> The agency proposed a {{convert|70|mi|km|adj=mid}} light rail network as the centerpiece of a $6.7&nbsp;billion transit ballot measure, with a surface line through the Rainier Valley and tunnels between Downtown Seattle, Capitol Hill, and the University District.<ref>{{cite news |last=Lilly |first=Dick |date=April 5, 1994 |title=Light-rail option would traverse Rainier Valley |page=B3 |work=The Seattle Times}}</ref><ref>{{cite news |last=Schaefer |first=David |date=February 12, 1995 |title=On the right track? Questions, answers to the $6.7 billion proposal |page=A1 |work=The Seattle Times}}</ref> The ballot measure failed to pass on March 14, 1995,<ref>{{cite news |last1=Schaefer |first1=David |last2=Murakami |first2=Kery |date=March 15, 1995 |title=Transit plan derailed: Pierce, Snohomish county voters say no to $6.7 billion proposal |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=19950315&slug=2110262 |url-status=live |access-date=January 18, 2018 |archive-url=https://web.archive.org/web/20180119063248/http://community.seattletimes.nwsource.com/archive/?date=19950315&slug=2110262 |archive-date=January 19, 2018}}</ref> and the light rail line was shortened to {{convert|25|mi|km}}, between the University District and Sea-Tac Airport.<ref name="Times-1996Oct">{{cite news |last=Schaefer |first=David |date=October 6, 1996 |title=Looking at the new transit proposal |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=19961006&slug=2352937 |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154404/http://community.seattletimes.nwsource.com/archive/?date=19961006&slug=2352937 |archive-date=September 18, 2017}}</ref> Voters approved the $3.9&nbsp;billion package on November 5, 1996, along with increases to sales taxes and motor vehicle [[excise tax]]es across the regional transit district.<ref name="Times-1996Oct"/><ref>{{cite news |last=Schaefer |first=David |date=November 6, 1996 |title=Voters back transit plan on fourth try |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=19961106&slug=2358535 |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20160303215211/http://community.seattletimes.nwsource.com/archive/?date=19961106&slug=2358535 |archive-date=March 3, 2016}}</ref> Sound Transit considered several routing options during a series of public hearings and studies early into the project's [[environmental impact]] study,<ref>{{cite news |last=Schaefer |first=David |date=December 10, 1997 |title=Residents debate light-rail route: under or out of our neighborhood, some say |page=B1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=19971210&slug=2577212 |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170814135107/http://community.seattletimes.nwsource.com/archive/?date=19971210&slug=2577212 |archive-date=August 14, 2017}}</ref> which adopted the name "Central Link".<ref>{{cite web |date=May 14, 1998 |title=Sound Transit Motion No. M98-40 |url=https://www.soundtransit.org/sites/default/files/documents/pdf/about/board/motions/1998/motion20no20m98-40.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170913064731/https://www.soundtransit.org/sites/default/files/documents/pdf/about/board/motions/1998/motion20no20m98-40.pdf |archive-date=September 13, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> In 1999, Sound Transit selected the alignment for the light rail project, consisting of a line between the University District and Sea-Tac Airport, with surface segments passing through [[Tukwila, Washington|Tukwila]], the Rainier Valley, and [[SoDo, Seattle|SoDo]], and tunnels under [[Beacon Hill, Seattle|Beacon Hill]], [[First Hill, Seattle|First Hill]], Capitol Hill, and [[Portage Bay]].<ref>{{cite press release |author=<!--Staff writer(s); no by-line.--> |date=November 18, 1999 |title=Sound Transit Board achieves historic milestone by selecting route for central Link light rail |url=http://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Sound-Transit-Board-achieves-historic-milestone-by-selecting-route-for-central-Link-light-rail |location=Seattle, Washington |publisher=Sound Transit |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20160303220828/http://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Sound-Transit-Board-achieves-historic-milestone-by-selecting-route-for-central-Link-light-rail |archive-date=March 3, 2016}}</ref>

===Budget issues and delays===

The Central Link project was originally planned to open in 2006 and projected to cost $1.9&nbsp;billion (equivalent to ${{Format price|{{Inflation|US-GDP|1900000000|1996}}}} in {{Inflation-year|US-GDP}} dollars),{{inflation-fn|US-GDP}} but the estimates were found to be unrealistic by auditors in November 2000.<ref>{{cite news |date=December 13, 2000 |title=Light-rail costs soars $1 billion |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20001213&slug=TTGI2KF2J |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20160114231022/http://community.seattletimes.nwsource.com/archive/?date=20001213&slug=TTGI2KF2J |archive-date=January 14, 2016}}</ref> New executives, hired by Sound Transit to replace previous program directors, presented a revised plan with an opening date pushed back three years to 2009 and a $3.8&nbsp;billion (equivalent to ${{Format price|{{Inflation|US-GDP|3800000000|2000}}}} in {{Inflation-year|US-GDP}} dollars) cost estimate.{{inflation-fn|US-GDP}}<ref>{{cite news |last=Garber |first=Andrew |date=January 18, 2001 |title=Congressman wants to delay light-rail money |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20010118&slug=sound18m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154436/http://community.seattletimes.nwsource.com/archive/?date=20010118&slug=sound18m |archive-date=September 18, 2017}}</ref> Planning of the Portage Bay tunnel between Capitol Hill and the University District was suspended due to higher than expected contractor bids, attributed to difficult soil conditions.<ref>{{cite news |last=Dudley |first=Brier |date=November 18, 2000 |title=Price puts tunnel on hold |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20001117&slug=4053431 |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170814145208/http://community.seattletimes.nwsource.com/archive/?date=20001117&slug=4053431 |archive-date=August 14, 2017}}</ref> Sound Transit adopted the revised budget and schedule in January 2001, including provisions to re-study routing options between Downtown Seattle and the University District, along with a $500&nbsp;million federal grant agreement to fund the construction of an "initial segment" for the project.<ref>{{cite news |last=Garber |first=Andrew |date=January 20, 2001 |title=Half-billion allocated for Sound Transit |page=B1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20010120&slug=sound20m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154250/http://community.seattletimes.nwsource.com/archive/?date=20010120&slug=sound20m |archive-date=September 18, 2017}}</ref><ref>{{cite web |date=February 2014 |title=Central Link Initial Segment and Airport Link Before and After Study – Final Report |url=http://www.wsdot.wa.gov/partners/erp/Letters/Attach7%20Initial%20Light%20Rail%20Segment%20Before%20and%20After%20Study%20Final%20Report%20(2).pdf |access-date=March 21, 2018 |publisher=Sound Transit |page=1 |via=Washington State Department of Transportation}}</ref> The initial segment identified and approved by Sound Transit later that year shortened the line to {{convert|14|mi}}, between Downtown Seattle and a [[Tukwila International Boulevard station|southern Tukwila station]] near Sea-Tac Airport. The remaining routes to the airport and University District were sent back to the planning stage, and re-organized into separate light rail projects.<ref>{{cite news |last=Garber |first=Andrew |date=September 26, 2001 |title=Sound Transit says it can build 14-mile line; light rail stops short of airport |page=B1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20010913&slug=transit13m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170106174736/http://community.seattletimes.nwsource.com/archive/?date=20010913&slug=transit13m |archive-date=January 6, 2017}}</ref><ref>{{cite news |last=Garber |first=Andrew |date=September 28, 2001 |title=Shorter light-rail line OK'd |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20010928&slug=sound28m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170107102057/http://community.seattletimes.nwsource.com/archive/?date=20010928&slug=sound28m |archive-date=January 7, 2017}}</ref>

In November 2001, Sound Transit approved construction of the shortened Central Link light rail project, calling for a summer 2002 groundbreaking.<ref>{{cite news |last=Pryne |first=Eric |date=November 30, 2001 |title=Sound Transit adopts 14-mile route; light-rail construction could start in summer |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20011130&slug=sound30m0 |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170106174621/http://community.seattletimes.nwsource.com/archive/?date=20011130&slug=sound30m0 |archive-date=January 6, 2017}}</ref> Property acquisition in the Rainier Valley began in March 2002,<ref>{{cite news |last=Pryne |first=Eric |date=March 15, 2002 |title=Sound Transit gets green light to buy land for light rail |page=B1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20020315&slug=sound15m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170107102036/http://community.seattletimes.nwsource.com/archive/?date=20020315&slug=sound15m |archive-date=January 7, 2017}}</ref> but two legal battles delayed the start of construction. In November 2002, the [[King County Superior Court]] ruled in favor of Sound Transit in a lawsuit filed by light rail opponents, alleging that it lacked the authority to shorten a voter-approved line.<ref>{{cite news |last=Lindblom |first=Mike |date=November 2, 2002 |title=Sound Transit gets light-rail go-ahead |page=B1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20021102&slug=sound02m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154403/http://community.seattletimes.nwsource.com/archive/?date=20021102&slug=sound02m |archive-date=September 18, 2017}}</ref> The approval of [[Tim Eyman]]'s Initiative 776 threatened to repeal motor vehicle excise taxes needed to fund Sound Transit's budget, but was declared unconstitutional in February 2003.<ref>{{cite news |last=Gilmore |first=Susan |date=February 11, 2003 |title=Judge tosses out $30 tabs |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20030211&slug=initiative11m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154707/http://community.seattletimes.nwsource.com/archive/?date=20030211&slug=initiative11m |archive-date=September 18, 2017}}</ref> Another routing change requested by the City of Tukwila, placing light rail tracks along freeways in lieu of International Boulevard, was approved by Sound Transit and the [[Federal Transit Administration]] in 2002, moving the project closer to construction.<ref>{{cite news |last=Pryne |first=Eric |date=June 29, 2002 |title=Sound Transit's hopes revived; Tukwila's approval 'not required' |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20020629&slug=tukwila29m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170106174942/http://community.seattletimes.nwsource.com/archive/?date=20020629&slug=tukwila29m |archive-date=January 6, 2017}}</ref>

===Construction and testing===
[[File:Beacon Hill Station - under construction, May 2009.jpg|alt=An unfinished building surrounded by a fenced-off dirt lot|left|thumb|The [[headhouse]] of [[Beacon Hill station (Sound Transit)|Beacon Hill station]], seen under construction in May 2009.]]

Sound Transit received its $500&nbsp;million federal grant agreement in October 2003,<ref>{{cite news |last=Lindblom |first=Mike |date=October 24, 2003 |title=Light-rail construction could begin in two weeks |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20031024&slug=sound24m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154510/http://community.seattletimes.nwsource.com/archive/?date=20031024&slug=sound24m |archive-date=September 18, 2017}}</ref> and a groundbreaking ceremony was held in SoDo on November 8, 2003.<ref>{{cite news |last=Lindblom |first=Mike |date=November 8, 2003 |title=Groundbreaking today for light rail |page=B1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20031108&slug=lightrail09m0 |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20141012221700/http://community.seattletimes.nwsource.com/archive/?date=20031108&slug=lightrail09m0 |archive-date=October 12, 2014}}</ref> Construction contracts for various segments were awarded in 2004 and 2005, coming six percent under Sound Transit's estimates,<ref name="ST-2005Rail">{{cite press release |date=August 18, 2005 |title=Sound Transit installs first rails for Central Link light rail line |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Sound-Transit-installs-first-rails-for-Central-Link-light-rail-line |publisher=Sound Transit |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170728142342/https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Sound-Transit-installs-first-rails-for-Central-Link-light-rail-line |archive-date=July 28, 2017}}</ref> and work began along all parts of the system.<ref>{{cite news |last=Robinson |first=Lauren |date=September 16, 2004 |title=Light-rail line hits fast forward |work=[[Seattle Daily Journal of Commerce]] |url=http://www.djc.com/news/co/11161149.html |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154221/http://www.djc.com/news/co/11161149.html |archive-date=September 18, 2017}}</ref><ref>{{cite web |date=March 10, 2005 |title=Sound Transit Board Meeting Summary Minutes |url=https://www.soundtransit.org/sites/default/files/documents/pdf/about/board/050310brd.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170917202137/https://www.soundtransit.org/sites/default/files/documents/pdf/about/board/050310brd.pdf |archive-date=September 17, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> The first rails were installed on August 18, 2005, in the SoDo area;<ref name="ST-2005Rail"/> a month later, the downtown transit tunnel closed for a two-year renovation to accommodate light rail service.<ref>{{cite news |last=Gilmore |first=Susan |date=September 23, 2005 |title=Bus tunnel shuts down tonight for 2 years |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2002514381_bustunnel23m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170202060355/http://old.seattletimes.com/html/localnews/2002514381_bustunnel23m.html |archive-date=February 2, 2017}}</ref> Excavation of the [[Beacon Hill tunnel (Seattle)|Beacon Hill tunnel]] and station began in 2005, and two [[tunnel boring machine]]s were launched in early 2006 to bore the twin tunnels between SoDo and the Rainier Valley.<ref>{{cite news |last1=Gildner |first1=Joe |last2=Sage |first2=Dick |date=March 23, 2006 |title=Sound Transit digs a cutting-edge tunnel |work=Seattle Daily Journal of Commerce |url=http://www.djc.com/news/co/11176943.html |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154255/http://www.djc.com/news/co/11176943.html |archive-date=September 18, 2017}}</ref>

The SODO and Stadium stations were completed in May 2006,<ref>{{cite press release |date=May 30, 2006 |title=Sound Transit completes first two Central Link light rail stations |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Sound-Transit-completes-first-two-Central-Link-light-rail-stations |publisher=Sound Transit |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170728134646/https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Sound-Transit-completes-first-two-Central-Link-light-rail-stations |archive-date=July 28, 2017}}</ref> and light rail testing in the SoDo area began the following March.<ref name="Lindblom B2">{{cite news |last=Lindblom |first=Mike |date=March 16, 2007 |title=Sound Transit begins light-rail train tests in Sodo |page=B2 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2003620720_railsafety16m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170917213803/http://old.seattletimes.com/html/localnews/2003620720_railsafety16m.html |archive-date=September 17, 2017}}</ref> Testing was extended to the re-opened downtown transit tunnel in September 2007, initially limited to weekends without bus service,<ref>{{cite web |date=August 2007 |title=Downtown Seattle Transit Tunnel to reopen Sept. 24 |url=http://metro.kingcounty.gov/up/sc/rideralert/pdf/TunnelReopeningFINAL.pdf |url-status=live |archive-url=https://web.archive.org/web/20161224131321/http://metro.kingcounty.gov/up/sc/rideralert/pdf/TunnelReopeningFINAL.pdf |archive-date=December 24, 2016 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> and further to the Rainier Valley after the completion of the Beacon Hill tunnel in 2008.<ref>{{cite press release |date=March 4, 2008 |title=Tunnel boring machine completes second Beacon Hill light rail tunnel |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/2ndTubeBreakthru |publisher=Sound Transit |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170918112239/https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/2ndTubeBreakthru |archive-date=September 18, 2017}}</ref><ref>{{cite news |last=Lindblom |first=Mike |date=August 13, 2008 |title=Sound Transit to run test trains through Rainier Valley |page=B1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2008109935_traintest13m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170105235324/http://old.seattletimes.com/html/localnews/2008109935_traintest13m.html |archive-date=January 5, 2017}}</ref> The elevated guideway in Tukwila, including crossings over major freeways and the [[Duwamish River]], was completed in 2007 after the installation of 2,457 precast concrete segments and balanced [[cantilever bridge]]s.<ref>{{cite press release |date=September 27, 2007 |title=Sound Transit completes construction of elevated light rail trackway between Seattle and Tukwila |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Completion-of-Elevated |publisher=Sound Transit |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170918110643/https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Completion-of-Elevated |archive-date=September 18, 2017}}</ref> During construction in the Rainier Valley, Sound Transit and the City of Seattle offered $50&nbsp;million in mitigation funds and development opportunities to affected businesses.<ref>{{cite news |last=Lindblom |first=Mike |date=March 30, 2006 |title=Rail work clogs the way on MLK |page=A1 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20060330&slug=rainiervalley30m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154709/http://community.seattletimes.nwsource.com/archive/?date=20060330&slug=rainiervalley30m |archive-date=September 18, 2017}}</ref> Construction of light rail along Martin Luther King Jr. Way South also resulted in utility lines being moved underground, improved sidewalks, street crossings, and landscaping.<ref>{{cite news |last=Earl |first=Joni |date=July 16, 2009 |title=6 years and $2.4B later, Central Link ready to roll |work=Seattle Daily Journal of Commerce |url=http://www.djc.com/news/co/12008112.html |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154332/http://www.djc.com/news/co/12008112.html |archive-date=September 18, 2017}}</ref>

===Opening and first extensions===
[[File:Link Light Rail crosses the Duwamish 04.jpg|thumb|The high bridge here crosses the [[Duwamish River]] in Tukwila; the low bridge carries East Marginal Way S.]]

Central Link was opened on July 18, 2009, with a community celebration that attracted more than 92,000 riders over the first weekend of free service.<ref name="Times-12K">{{cite news |last=Lindblom |first=Mike |date=July 30, 2009 |title=Light rail averaging 12,000 riders per weekday so far |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009570527_webstridership31m.html |url-status=dead |access-date=August 25, 2016 |archive-url=https://web.archive.org/web/20160816235517/http://old.seattletimes.com/html/localnews/2009570527_webstridership31m.html |archive-date=August 16, 2016}}</ref> Trains began operating on the {{convert|13.9|mi|km|1|adj=mid}} segment between {{stn|Westlake||Sound Transit}} and {{stn|Tukwila International Boulevard}} stations,<ref>{{cite web |date=June 2016 |title=Central Puget Sound Regional Transit Authority 2016 Financial Plan |url=https://www.soundtransit.org/sites/default/files/2016-Financial-Plan.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170918032734/https://www.soundtransit.org/sites/default/files/2016-Financial-Plan.pdf |archive-date=September 18, 2017 |access-date=September 17, 2017 |publisher=Sound Transit |page=16}}</ref> along with a bus shuttle to serve Sea-Tac Airport from Tukwila.<ref>{{cite news |last=Lindblom |first=Mike |date=July 20, 2009 |title=Light-rail trains run smoothly, if not to capacity, on first day |page=B1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009503977_websoundtransit20m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20161128135143/http://old.seattletimes.com/html/localnews/2009503977_websoundtransit20m.html |archive-date=November 28, 2016}}</ref> The {{convert|1.7|mi|km|adj=mid}} extension to [[SeaTac/Airport station]] opened on December 19, 2009, replacing the shuttle and other bus services to the airport.<ref>{{cite news |last=Lindblom |first=Mike |date=December 17, 2009 |title=Airport rail station opens Saturday |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2010527454_airportlink17m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170116200835/http://old.seattletimes.com/html/localnews/2010527454_airportlink17m.html |archive-date=January 16, 2017}}</ref> Sound Transit added lubrication equipment and rubber mats to segments in Tukwila and the Rainier Valley in 2010 to reduce noise levels that had reached up to 83 [[decibel]]s, surpassing federal safety standards and triggering noise complaints from nearby residents.<ref>{{cite news |last=Lindblom |first=Mike |date=April 4, 2010 |title=Sound Transit installs lube machines to quiet noisy tracks |page=B1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2011518119_tracklube04m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110615/http://old.seattletimes.com/html/localnews/2011518119_tracklube04m.html |archive-date=September 18, 2017}}</ref> A contract dispute with the Rainier Valley construction contractor was settled in 2011, bringing the project's total price to $117&nbsp;million below the $2.44&nbsp;billion budget.<ref>{{cite news |last=Lindblom |first=Mike |date=June 24, 2011 |title=Light-rail contract dispute is resolved |page=B1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2015410238_lightrail24m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110623/http://old.seattletimes.com/html/localnews/2015410238_lightrail24m.html |archive-date=September 18, 2017}}</ref> The opening of light rail service to the Rainier Valley spurred new [[transit-oriented development]], which had initially stalled during the [[Great Recession]] but recovered in the mid-2010s.<ref>{{cite news |last=McNichols |first=Joshua |date=February 26, 2015 |title=South Seattle Development Is Slow, Despite Promise Of Light Rail |publisher=[[KUOW-FM|KUOW]] |url=http://kuow.org/post/south-seattle-development-slow-despite-promise-light-rail |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170609210348/http://kuow.org/post/south-seattle-development-slow-despite-promise-light-rail |archive-date=June 9, 2017}}</ref><ref>{{cite news |last=Pryne |first=Eric |date=April 6, 2009 |title=Recession stalls building boom along South Seattle light-rail tracks |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2008990973_mlkrail06.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170510081149/http://old.seattletimes.com/html/localnews/2008990973_mlkrail06.html |archive-date=May 10, 2017}}</ref>

Central Link train service was increased to a frequency of 6 minutes during peak hours, from 7.5 minutes, in 2015 to prepare for the opening of the [[University Link extension]].<ref>{{cite news |last=Lindblom |first=Mike |date=September 17, 2015 |title=Light-rail trains to run every 6 minutes between Seattle and Sea-Tac |page=B1 |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/light-rail-trains-to-run-more-often/ |url-status=live |url-access=limited |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20161011023510/http://www.seattletimes.com/seattle-news/transportation/light-rail-trains-to-run-more-often/ |archive-date=October 11, 2016}}</ref> The line was extended north to [[University of Washington station]], via [[Capitol Hill station]], on March 19, 2016, via a $1.8&nbsp;billion, {{convert|3.15|mi|km|2|adj=mid}} tunnel.<ref>{{cite news |last=Beekman |first=Daniel |date=March 19, 2016 |title=Capitol Hill, UW light-rail stations open to big crowds |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/capitol-hill-uw-light-rail-stations-open/ |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170101203045/http://www.seattletimes.com/seattle-news/transportation/capitol-hill-uw-light-rail-stations-open/ |archive-date=January 1, 2017}}</ref> The extension opened six months ahead of its scheduled date, and the opening celebrations drew 67,000 people during the first day of service. Sound Transit deployed additional three-car light rail trains to cope with higher ridership after the extension opened.<ref>{{cite news |last=Lindblom |first=Mike |date=March 24, 2016 |title=Sound Transit to add longer trains to meet unexpected light-rail demand |page=B1 |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/sound-transit-to-add-bigger-trains-to-meet-ridership-demands/ |url-status=live |url-access=limited |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170911071146/http://www.seattletimes.com/seattle-news/transportation/sound-transit-to-add-bigger-trains-to-meet-ridership-demands/ |archive-date=September 11, 2017}}</ref> The line was extended {{convert|1.6|mi|km|1}} south from Sea-Tac Airport to [[Angle Lake station]] on September 24, 2016, including the opening of a 1,120-stall [[park and ride]].<ref>{{cite news |last=Lindblom |first=Mike |date=September 23, 2017 |title=Angle Lake light-rail station opens Saturday with party |page=B3 |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/angle-lake-station-opens-saturday-with-celebration/ |url-status=live |url-access=limited |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20160926094036/http://www.seattletimes.com/seattle-news/transportation/angle-lake-station-opens-saturday-with-celebration/ |archive-date=September 26, 2016}}</ref>

The escalators at Capitol Hill and University of Washington stations experienced several major failures and shutdowns in the two years since the University Link extension was opened. These failures were attributed to the installation of standard commercial escalators instead of stronger escalators designed for transit stations. A new escalator contractor was selected to provide preventative maintenance in lieu of a proposed replacement plan; new stairways and connecting passageways were also opened to allow for alternative access.<ref>{{cite news |last=Lindblom |first=Mike |date=October 25, 2018 |title=Sound Transit will add stairs and stronger escalators to fix UW Station breakdowns |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/sound-transit-will-add-stairs-and-stronger-escalators-to-fix-uw-station-breakdowns/ |url-access=limited |access-date=October 25, 2018}}</ref><ref>{{cite news |last=Merten |first=Paxtyn |date=October 7, 2020 |title=Sound Transit scraps plans to replace UW Station escalators, citing performance improvements |work=Puget Sound Business Journal |url=https://www.bizjournals.com/seattle/news/2020/10/07/uw-light-rail-station-escalators-replacement.html |access-date=September 13, 2021}}</ref> The Tukwila section of the line was shut down over one weekend in October 2018 for major repairs after cracks were discovered in the rails on the {{convert|1,200|ft|m|adj=mid}} bridge crossing [[Interstate 5 in Washington|Interstate 5]].<ref>{{cite news |last=Lindblom |first=Mike |date=October 2, 2018 |title=Cracks in light-rail tracks slow trains in South Seattle; expect closures for repairs over weekend |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/cracks-in-light-rail-tracks-slow-trains-in-south-seattle-expect-closures-for-repairs-over-weekend/ |url-access=limited |access-date=October 25, 2018}}</ref>

===Renaming and northern extensions===

Central Link was renamed to the "Red Line" as part of a systemwide rebranding in September 2019 by Sound Transit to prepare for the arrival of East Link (the Blue Line).<ref name="ST-Red">{{cite news |last=Netzler |first=Kat |date=September 18, 2019 |title=Link light rail debuts line colors |work=The Platform |publisher=Sound Transit |url=https://www.soundtransit.org/blog/platform/link-light-rail-debuts-line-colors |access-date=September 18, 2019}}</ref> Two months later, the agency announced that it would consider a new name after complaints due to the similarity of the "Red Line" with [[redlining]], which historically affected residents of the Rainier Valley.<ref>{{cite news |last=Martinez-Vasquez |first=Jackie |date=November 14, 2019 |title=Sound Transit will drop the "Red Line" name |work=The Platform |publisher=Sound Transit |url=https://www.soundtransit.org/blog/platform/sound-transit-will-drop-red-line-name |access-date=November 14, 2019}}</ref> A new designation, the 1{{nbsp}}Line (colored green), was announced in April 2020 and took effect in September 2021.<ref>{{cite news |last=Shaner |first=Zee |date=April 9, 2020 |title=New line names coming in 2021 |work=The Platform |publisher=Sound Transit |url=https://www.soundtransit.org/blog/platform/new-line-names-coming-2021 |access-date=April 9, 2020}}</ref><ref>{{cite news |last=Craighead |first=Callie |date=August 31, 2021 |title=Sound Transit gearing up to rebrand Seattle link light rail lines with new names, numbers and colors |work=Seattle Post-Intelligencer |url=https://www.seattlepi.com/local/transportation/article/sound-transit-renames-link-light-rail-lines-2021-16425400.php |access-date=September 1, 2021}}</ref>

In January 2020, Sound Transit began a ten-week construction project called "Connect 2020" that required trains to single-track in the Downtown Seattle Transit Tunnel. The closure of tracks for work on the [[2 Line (Sound Transit)|East Link Extension]] where it meets the existing tracks at International District/Chinatown necessitated the construction of a temporary [[center platform]] at Pioneer Square for use by through-riding passengers. Sound Transit deployed four-car trains running every 13–15 minutes and implemented restrictions on carrying bicyclists on trains through downtown.<ref name="Times-Connect">{{cite news |last=Lindblom |first=Mike |date=January 2, 2020 |title=Light-rail riders can expect more crowded, less frequent trains as downtown track construction begins |page=A1 |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/light-rail-riders-can-expect-more-crowded-less-frequent-trains-as-downtown-track-construction-begins/ |access-date=January 8, 2020}}</ref><ref>{{cite news |date=January 8, 2020 |title=Connect 2020 Link schedules adjusting to every 13-15 minutes |work=The Platform |publisher=Sound Transit |url=https://www.soundtransit.org/blog/platform/connect-2020-link-schedules-adjusting-to-every-13-15-minutes |access-date=January 8, 2020}}</ref> The project was completed in late March after a week-long delay in testing, but the frequency restrictions remained due to the [[2020 coronavirus pandemic in Washington (state)|COVID-19 pandemic]] and local shutdowns.<ref>{{cite press release |date=March 22, 2020 |title=Connect 2020 concludes, ending Link light rail transfers at Pioneer Square and bicycle restrictions |url=https://www.soundtransit.org/get-to-know-us/news-events/news-releases/connect-2020-concludes-ending-link-light-rail-transfers |publisher=Sound Transit |access-date=March 24, 2020}}</ref><ref>{{cite news |last1=Groover |first1=Heidi |last2=Baruchman |first2=Michelle |date=March 15, 2020 |title=Light rail service disruptions will continue after problems discovered during downtown track work |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/light-rail-service-disruptions-will-continue-after-problems-discovered-during-downtown-track-work/ |access-date=March 24, 2020}}</ref> Service was reduced to every 30 minutes in April and partially restored in September to every 8 minutes during peak hours and 15 minutes during most other hours.<ref>{{cite press release |date=April 16, 2020 |title=ST to temporarily reduce service further on Link and some ST Express routes |url=https://www.soundtransit.org/get-to-know-us/news-events/news-releases/st-to-temporarily-reduce-service-further-link-some-st |publisher=Sound Transit |access-date=September 1, 2020}}</ref><ref>{{cite press release |date=August 11, 2020 |title=Sound Transit to increase service on Link light rail effective September 19 |url=https://www.soundtransit.org/get-to-know-us/news-events/news-releases/sound-transit-to-increase-service-link-light-rail |publisher=Sound Transit |access-date=September 1, 2020}}</ref> The first of the new "Series&nbsp;2" light rail vehicles, based on the [[Siemens S700 and S70|Siemens S700]], entered service in May 2021.<ref name="RA-Siemens"/>

The third expansion of the 1{{nbsp}}Line, a {{convert|4.3|mi|km|adj=mid}} northern extension from University of Washington station to the [[Northgate, Seattle|Northgate]] neighborhood of Seattle, was funded by the [[Sound Transit 2]] ballot measure in 2008 and began construction in 2012.<ref name="RA-Northgate">{{cite news |last=Luczak |first=Marybeth |date=October 4, 2021 |title=Sound Transit Northgate Link LRT: 'Welcome Aboard' |work=Railway Age |url=https://www.railwayage.com/passenger/light-rail/sound-transit-northgate-link-lrt-welcome-aboard/ |access-date=October 9, 2021}}</ref> The {{convert|3.5|mi|km|adj=mid}} tunnel was excavated between July 2014 and September 2016 using two tunnel boring machines, creating a pair of bores between the extension's three stations.<ref>{{cite news |last=DeMay |first=Daniel |date=September 2, 2016 |title=Sound Transit completes tunneling for Northgate light rail extension |work=Seattle Post-Intelligencer |url=https://www.seattlepi.com/local/transportation/article/Sound-Transit-completes-tunneling-for-Northgate-9200711.php |access-date=October 9, 2021}}</ref> The southernmost section of the extension passes under the University of Washington campus and required several mitigation measures to reduce electromagnetic interference for laboratory equipment, including rubber dampeners on floating slabs of track and the relocation of sensitive equipment at four facilities.<ref>{{cite news |last=Long |first=Katherine |date=May 8, 2014 |title=$43 million deal to move UW labs for light-rail line |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/43-million-deal-to-move-uw-labs-for-light-rail-line/ |access-date=October 9, 2021}}</ref> The Northgate extension opened on October 2, 2021, adding three stations to the line's north end.<ref>{{cite press release |date=October 1, 2021 |title=Link light rail reaches Seattle's University District, Roosevelt and Northgate neighborhoods |url=https://www.soundtransit.org/get-to-know-us/news-events/news-releases/link-light-rail-reaches-seattles-university-district |publisher=Sound Transit |access-date=October 2, 2021}}</ref>

Service on the 1{{nbsp}}Line was disrupted several times in 2022 and 2023 by emergency repairs and maintenance projects that necessitated section closures and single-tracking with reduced frequencies. The [[tactile paving|tactile strip]] on the edge of platforms at several stations in the Rainier Valley was replaced after premature wear and cracking was discovered.<ref>{{cite news |last=Lindblom |first=Mike |date=June 21, 2022 |title=Cracked tiles mean light rail in Rainier Valley will run less often this summer |url=https://www.seattletimes.com/seattle-news/transportation/light-rail-trains-in-rainier-valley-to-run-less-often-this-summer/ |work=The Seattle Times |accessdate=September 17, 2023}}</ref> On April 27, 2023, the ceiling of Westlake station was punctured during surface construction and necessitated two weeks of service disruptions in Downtown Seattle, including a forced transfer at [[Pioneer Square station]].<ref>{{cite news |last=Lindblom |first=Mike |date=May 4, 2023 |title=How a demolition crew punctured the Westlake Station ceiling |url=https://www.seattletimes.com/seattle-news/transportation/how-a-demolition-crew-punctured-the-westlake-station-ceiling/ |work=The Seattle Times |accessdate=September 17, 2023}}</ref><ref>{{cite news |last=Blatchford |first=Taylor |date=May 7, 2023 |title=After ceiling puncture, Seattle light rail resuming normal service Monday |url=https://www.seattletimes.com/seattle-news/after-ceiling-puncture-seattle-light-rail-resuming-normal-service-monday/ |work=The Seattle Times |accessdate=September 17, 2023}}</ref> A grade crossing at Royal Brougham Way (adjacent to Stadium station) was replaced in August 2023 due to ground settling that had caused it to sink by {{convert|3|in|cm}}.<ref>{{cite news |last=Lindblom |first=Mike |date=August 8, 2023 |title=Severe shutdown ahead for Seattle light rail due to sinking tracks |url=https://www.seattletimes.com/seattle-news/transportation/severe-shutdown-ahead-for-seattle-light-rail-due-to-sinking-tracks/ |work=The Seattle Times |accessdate=September 17, 2023}}</ref> The project required trains to single-track and run with extensive delays, which continued during work at Othello and Rainier Beach stations that lasted until mid-September.<ref>{{cite news |last=Lindblom |first=Mike |date=August 29, 2023 |title=Signal woes delay Sound Transit trains during rush hour |url=https://www.seattletimes.com/seattle-news/transportation/signal-woes-delay-sound-transit-trains-during-rush-hour/ |work=The Seattle Times |accessdate=September 17, 2023}}</ref><ref>{{cite press release |date=September 14, 2023 |title=1 Line service returns to normal Saturday, Sept. 16 |url=https://www.soundtransit.org/get-to-know-us/news-events/news-releases/1-line-service-returns-to-normal-saturday-sept-16 |publisher=Sound Transit |accessdate=September 17, 2023}}</ref>

The [[Lynnwood Link Extension]] opened on August 30, 2024, adding four stations to the line as it crossed into [[Snohomish County, Washington|Snohomish County]]. It cost $3&nbsp;billion to construct the {{convert|8.5|mi|km|adj=mid}} extension and is expected to carry 50,000 daily passengers.<ref name="Times-Lynnwood2024">{{cite news |last1=Deshais |first1=Nicholas |last2=Lindblom |first2=Mike |date=August 30, 2024 |title=New light rail stations draw big crowds for first trips |url=https://www.seattletimes.com/seattle-news/transportation/new-light-rail-stations-draw-big-crowds-for-first-trips/ |work=The Seattle Times |accessdate=August 30, 2024}}</ref> On the same day, University Street station was renamed to [[Symphony station (Sound Transit)|Symphony]] to reduce confusion with the stations serving the University of Washington campus.<ref name="Times-Symphony">{{cite news |last=Lindblom |first=Mike |date=August 6, 2024 |title=This Seattle light rail station is getting renamed, clearing confusion |url=https://www.seattletimes.com/seattle-news/transportation/this-seattle-light-rail-station-is-getting-renamed-clearing-confusion/ |accessdate=September 4, 2024}}</ref> The full 2{{nbsp}}Line between Seattle and the Eastside was planned to open before Lynnwood and provide access to a new operations and maintenance facility in Bellevue. To maintain eight-minute frequencies with four-car trains, some vehicles will be parked outside of the SODO facility and evening service is planned to be reduced; some bus service on the corridor is planned to be retained to accommodate overflow passengers.<ref>{{cite news |last=Lindblom |first=Mike |date=March 8, 2024 |title=Sound Transit pulls out the stops to solve a Lynnwood train shortage |url=https://www.seattletimes.com/seattle-news/transportation/sound-transit-pulls-out-the-stops-to-solve-a-lynnwood-train-shortage/ |work=The Seattle Times |accessdate=March 9, 2024}}</ref> The line is planned to later have trains every eight minutes at peak and ten minutes mid-day and on weekends, with a combined frequency of four minutes at peak and five minutes off-peak between International District/Chinatown and Lynnwood City Center stations on both lines.<ref>{{cite web |date=February 2023 |title=Lynnwood Link Extension: Northgate to Lynnwood City Center |url=https://kingcounty.gov/~/media/depts/metro/programs-projects/link-connections/lynnwood-link/pdf/routes/link-light-rail.pdf |work=Lynnwood Link Connections |publisher=King County Metro |access-date=February 3, 2023}}</ref>

==Route==
[[File:Link light rail, route map.png|alt=A map depicting the route of the 1{{nbsp}}Line through Seattle, with stations marked and labeled.|right|thumb|A map of the 1 Line, showing the line before the opening of the [[Lynnwood Link extension]] in 2024. Four new stations have since opened north of Northgate.]]

The northern terminus of the 1 Line is [[Lynnwood City Center station]], located at the southern end of Downtown [[Lynnwood, Washington|Lynnwood]] next to Interstate 5 in [[Snohomish County, Washington|Snohomish County]]. The line leaves Lynnwood southwest on an elevated guideway that follows the western edge of Interstate 5 from 208th Street Southwest until it enters [[Mountlake Terrace, Washington|Mountlake Terrace]] at 212th Street Southwest. There, it descends to the surface—aside from an elevated section over 220th Street Southwest—and continues following Interstate 5 until it crosses over the highway to serve [[Mountlake Terrace station]].<ref name="LLE-EIS"/> From Mountlake Terrace, the line crosses south over [[Washington State Route 104|State Route 104]] into [[Shoreline, Washington|Shoreline]] and [[King County, Washington|King County]], descending to the surface to follow the eastern edge of Interstate 5 and serve [[Shoreline North/185th station]]. It then continues south until it reaches the elevated [[Shoreline South/148th station]]; the latter Shoreline station will serve as a transfer to the future [[Stride S3 Line]]. The line leaves Shoreline elevated into Seattle, passing through provisions made for a future [[NE 130th Street station|infill station]] at Northeast 130th Street before descending to a surface alignment. The line continues at-grade until it approaches the elevated [[Northgate station (Sound Transit)|Northgate Station]], located adjacent to [[Northgate Station (shopping mall)|Northgate Mall]].<ref name="LLE-EIS">{{cite report |author=Sound Transit
|date=April 2015 |title=Lynnwood Link Extension Final Environmental Impact Statement |url=https://www.soundtransit.org/get-to-know-us/documents-reports/april-2015-lynnwood-link-extension-environmental-impact-statement |access-date=September 7, 2024}}</ref><ref name="LLE-EIS-SEPA">{{cite report |author=Sound Transit
|date=May 2018 |title=2018 SEPA Addendum to the Lynnwood Link Extension Final Environmental Impact Statement (April 2015) |url=https://www.soundtransit.org/sites/default/files/lynnwood-link-extension-SEPA-May-2018.pdf |access-date=September 7, 2024}}</ref>

From Northgate station, the line continues south elevated before diving into the [[Northgate Link tunnel]] in the [[Maple Leaf, Seattle|Maple Leaf]] neighborhood. The {{convert|3.4|mi|km|adj=mid}} tunnel travels southeast through [[Roosevelt, Seattle|Roosevelt]], serving a [[Roosevelt station (Sound Transit)|station]] near Northeast 65th Street, and south to [[U District station]] before reaching the [[University of Washington campus]].<ref>{{cite news |last=Lindblom |first=Mike |date=March 17, 2015 |title=Transit-tunnel machine reaches daylight at Roosevelt Station |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/transit-tunnel-machine-reaches-daylight-at-roosevelt-station/ |access-date=October 2, 2021}}</ref><ref>{{cite news |last=Morgan |first=Rick |date=April 9, 2021 |title=Sound Transit sets opening date for Northgate light rail extension |work=Puget Sound Business Journal |url=https://www.bizjournals.com/seattle/news/2021/04/09/northgate-link-extension-date-set.html |access-date=October 9, 2021}}</ref> The tunnel travels southeast under the campus to University of Washington station, located near [[Husky Stadium]], from which it heads south in the [[University Link tunnel]], crossing under the [[Montlake Cut]] of the [[Lake Washington Ship Canal]] and [[Washington State Route 520|State Route 520]] before taking a turn to the southwest. The tunnel climbs [[Capitol Hill (Seattle)|Capitol Hill]] and passes under [[Interlaken Park]] and [[Volunteer Park (Seattle)|Volunteer Park]] before turning due south to enter Capitol Hill station on the east side of [[Broadway (Seattle)|Broadway]].<ref>{{cite map |date=May 2011 |title=Light-rail link to UW |url=http://seattletimes.nwsource.com/ABPub/2011/05/16/2015068417.pdf |publisher=The Seattle Times|access-date=September 17, 2017|url-status=live|archive-url=https://web.archive.org/web/20110813100125/http://seattletimes.nwsource.com/ABPub/2011/05/16/2015068417.pdf|archive-date=August 13, 2011}}</ref> The tunnel makes a gradual turn to the west, dipping as far south as East Union Street, and crosses under [[Interstate 5 in Washington|Interstate 5]] at Pine Street.<ref name="ST-LinkMap">{{cite map |title=Link light rail |url=https://www.soundtransit.org/schedules/light-rail/link-light-rail/map |publisher=Sound Transit |cartography=[[Bing Maps]]|access-date=September 17, 2017|url-status=live|archive-url=https://web.archive.org/web/20170918110453/https://www.soundtransit.org/schedules/light-rail/link-light-rail/map|archive-date=September 18, 2017}}</ref><ref>{{cite map |date=January 2007 |title=University Link Light Rail |url=https://www.soundtransit.org/sites/default/files/documents/pdf/projects/link/north/ULink/ULinkStreetmap1_07.pdf |publisher=Sound Transit|access-date=September 17, 2017|url-status=dead|archive-url=https://web.archive.org/web/20150910080505/http://www.soundtransit.org/sites/default/files/documents/pdf/projects/link/north/ULink/ULinkStreetmap1_07.pdf|archive-date=September 10, 2015}}</ref> It merges into the Downtown Seattle Transit Tunnel within the Pine Street Stub Tunnel, where it formerly merged with buses from [[Convention Place station]].<ref>{{cite web |date=November 30, 2012 |title=Pine Street Stub Tunnel |url=https://www.soundtransit.org/sites/default/files/documents/pdf/archived_projects/20121130_pinestreetstubtunnel.pdf |url-status=dead |archive-url=https://web.archive.org/web/20150909221125/http://www.soundtransit.org/sites/default/files/documents/pdf/archived_projects/20121130_pinestreetstubtunnel.pdf |archive-date=September 9, 2015 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref><ref name="DSTTMap">{{cite map |title=Downtown Seattle Transit Tunnel |url=http://metro.kingcounty.gov/maps/pdf/downtown-seattle-tunnel-map.pdf |publisher=[[King County Metro]]|access-date=September 17, 2017|url-status=live|archive-url=https://web.archive.org/web/20141006083234/http://metro.kingcounty.gov/maps/pdf/downtown-seattle-tunnel-map.pdf|archive-date=October 6, 2014}}</ref>

The downtown transit tunnel, formerly shared between light rail trains and buses,<ref>{{cite news |last=Lindblom |first=Mike |date=May 21, 2009 |title=Tunnel two-step: It may take buses longer to clear shared tunnel |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009245404_stdowntown21m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170905094130/http://old.seattletimes.com/html/localnews/2009245404_stdowntown21m.html |archive-date=September 5, 2017}}</ref> travels west under Pine Street through Westlake station and south on 3rd Avenue through [[Symphony station (Sound Transit)|Symphony]] and [[Pioneer Square station|Pioneer Square]] stations in [[Downtown Seattle]].<ref name="DSTTMap"/> The tunnel ends at [[International District/Chinatown station]], adjacent to [[King Street Station]] (served by [[Amtrak]] and [[Sounder commuter rail]]),<ref>{{cite map |date=October 2015 |title=Transit Tunnel: International District/Chinatown Station |url=http://metro.kingcounty.gov/tops/tunnel/pdf/ID_ChinatownMap.pdf |publisher=King County Metro|access-date=September 17, 2017|url-status=live|archive-url=https://web.archive.org/web/20151123200507/http://metro.kingcounty.gov/tops/tunnel/pdf/ID_ChinatownMap.pdf|archive-date=November 23, 2015}}</ref> and the 1{{nbsp}}Line travels south through SoDo along the east side of the [[SODO Busway]]. The SoDo section has two stations, [[Stadium station (Sound Transit)|Stadium]] and [[SODO station (Sound Transit)|SODO]], and includes several [[Boom barrier|gated crossings]].<ref name="Lindblom B2"/> From SODO station, the track ascends to an elevated guideway traveling east along South Forest Street,<ref name="ST-LinkMap"/><ref name="Times-Map">{{cite map |last=Nowlin |first=Mark |date=July 12, 2009 |title=Your guide to riding light rail |work=The Seattle Times |url=http://seattletimes.nwsource.com/flatpages/local/lightrailinteractive.html|url-status=dead|archive-url=https://web.archive.org/web/20090715003858/http://seattletimes.nwsource.com/flatpages/local/lightrailinteractive.html|archive-date=July 15, 2009|access-date=September 17, 2017}}</ref> passing the line's [[railyard]] and maintenance facility.<ref>{{cite web |date=November 30, 2012 |title=Link Light Rail Operations & Maintenance Facility |url=https://www.soundtransit.org/sites/default/files/documents/pdf/archived_projects/20121130_linklightrailoperationsandmaintenancefacility.pdf |url-status=dead |archive-url=https://web.archive.org/web/20150921005144/http://www.soundtransit.org/sites/default/files/documents/pdf/archived_projects/20121130_linklightrailoperationsandmaintenancefacility.pdf |archive-date=September 21, 2015 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> The elevated trackway passes over Airport Way and comes to rest on an embankment under Interstate 5, entering the Beacon Hill tunnel.<ref>{{cite web |date=November 30, 2012 |title=Beacon Hill Tunnel & Station |url=https://www.soundtransit.org/sites/default/files/documents/pdf/archived_projects/20121130_beaconhilltunnelandstation.pdf |url-status=dead |archive-url=https://web.archive.org/web/20150909225511/http://www.soundtransit.org/sites/default/files/documents/pdf/archived_projects/20121130_beaconhilltunnelandstation.pdf |archive-date=September 9, 2015 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref><ref>{{cite map |date=September 2016 |title=Metro Transit System: Northwest Area |url=http://metro.kingcounty.gov/maps/system/2016/sept/metro-system-map-northwest.pdf |publisher=King County Metro|access-date=September 17, 2017|url-status=dead|archive-url=https://web.archive.org/web/20180102035742/http://metro.kingcounty.gov/maps/system/2016/sept/metro-system-map-northwest.pdf|archive-date=January 2, 2018}}</ref>

The Beacon Hill tunnel travels approximately {{convert|1|mi|km|1|spell=in}} under [[Beacon Hill, Seattle|Beacon Hill]], serving [[Beacon Hill station (Sound Transit)|a station]] at Beacon Avenue South.<ref>{{cite news |last=Lindblom |first=Mike |date=June 15, 2009 |title=Beacon Hill's light-rail station filled with colorful art |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009338837_stbeaconhill15m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20161011160505/http://old.seattletimes.com/html/localnews/2009338837_stbeaconhill15m.html |archive-date=October 11, 2016}}</ref> Trains exit the tunnel on the east side of the hill, turning southeast and approaching the elevated [[Mount Baker station]] at the intersection of Rainier Avenue South and Martin Luther King Jr. Way South.<ref>{{cite news |last=Lindblom |first=Mike |date=June 22, 2009 |title=Revamped bus routes to carry commuters to Mount Baker light-rail station |page=B1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009367129_stmountbaker22m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110634/http://old.seattletimes.com/html/localnews/2009367129_stmountbaker22m.html |archive-date=September 18, 2017}}</ref> Light rail trains descend from Mount Baker station onto the [[Median (road)|median]] of Martin Luther King Jr. Way South, running at-grade with [[Transit signal priority|signal priority]] at 28 street crossings.<ref name="Times-2009Aboard">{{cite news |last=Lindblom |first=Mike |date=July 12, 2009 |title=All aboard, Seattle: You're a light-rail town now |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009456949_stlightrail12.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110632/http://old.seattletimes.com/html/localnews/2009456949_stlightrail12.html |archive-date=September 18, 2017}}</ref><ref>{{cite news |last=Brown |first=Charles E. |date=April 27, 2009 |title=Some drivers see red over light rail's impact on traffic lights |page=B1 |work=The Seattle Times |url=http://old.seattletimes.com/html/bumpertobumper/2009127353_bumper27m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110614/http://old.seattletimes.com/html/bumpertobumper/2009127353_bumper27m.html |archive-date=September 18, 2017}}</ref> The 1{{nbsp}}Line passes through the Rainier Valley and serves three at-grade stations, {{stn|Columbia City}}, {{stn|Othello}}, and {{stn|Rainier Beach}}, before leaving Seattle.<ref name="ST-LinkMap"/><ref>{{cite map |date=February 2, 2004 |title=Rainier Valley Link Light Rail Route & Stations |publisher=Sound Transit |url=http://www.soundtransit.org/pdf/projects/link/LinkRV_map_1_05.pdf|url-status=dead|archive-url=https://web.archive.org/web/20060208224439/http://www.soundtransit.org/pdf/projects/link/LinkRV_map_1_05.pdf|archive-date=February 8, 2006 |oclc=49259323|access-date=September 17, 2017}}</ref>

The line enters Tukwila and crosses west over Interstate 5 and a mainline railroad at Boeing Access Road, near [[Boeing Field]], before making a southward turn over East Marginal Way South. The 1{{nbsp}}Line continues south over the Duwamish River, traveling non-stop through Tukwila on a {{convert|4.7|mi|km|adj=mid}} elevated guideway.<ref>{{cite news |last=Hubbard |first=Ian |date=July 16, 2009 |title=The long bridge to Tukwila |work=Seattle Daily Journal of Commerce |url=http://www.djc.com/news/co/12008114.html |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170814020144/http://www.djc.com/news/co/12008114.html |archive-date=August 14, 2017}}</ref> The guideway runs along the west sides of [[Washington State Route 599|State Route 599]] and Interstate 5 towards [[Southcenter Mall]], where it turns west along [[Washington State Route 518|State Route 518]]. The line passes through Tukwila International Boulevard station, home to a 600-stall park and ride facility, and turns south into the median of the [[Airport Expressway (Seattle)|Airport Expressway]] towards [[SeaTac, Washington|SeaTac]]. Light rail trains continue along the east side of Seattle–Tacoma International Airport, stopping at SeaTac/Airport station near the airport's terminals, before reaching [[Angle Lake station]], where it terminates.<ref name="ST-LinkMap"/><ref name="Times-Map"/>

The 1{{nbsp}}Line, while officially a "light rail" line, has also been described as a "[[light metro]]" hybrid by transit experts due to its [[Grade separation|grade separated]] sections and use of longer trainsets than typical American light rail systems.<ref name="Times-2009Aboard"/> It is {{convert|33.15|mi|km}} long and includes {{convert|7|mi|km}} of at-grade tracks;<ref name="SafetyPlan">{{cite report |date=September 2024 |title=Sound Transit Agency Safety Plan |pages=43–48 |url=https://www.soundtransit.org/st_sharepoint/download/sites/PRDA/ActiveDocuments/Report%20-%20Agency%20Safety%20Plan%20September%202024%20-%2009-23-24.pdf |publisher=Sound Transit |accessdate=September 26, 2024}}</ref> these at-grade tracks include some segments along freeways that are separated from intersecting roads.<ref>{{cite news |last=Cowan |first=Nils |date=October 5, 2016 |title=Sound Transit 3: Proposition 1 Hopes to Create a Regional Rail Network |publisher=[[KCTS-TV]] |url=https://kcts9.org/programs/in-close/sound-transit-3-proposition-1-hopes-create-regional-rail-network |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154414/https://kcts9.org/programs/in-close/sound-transit-3-proposition-1-hopes-create-regional-rail-network |archive-date=September 18, 2017}}</ref><ref name="BeforeAfter">{{cite report |url=http://www.wsdot.wa.gov/partners/erp/Letters/Attach7%20Initial%20Light%20Rail%20Segment%20Before%20and%20After%20Study%20Final%20Report%20(2).pdf |title=Central Link Initial Segment and Airport Link Before & After Study: Final Report |date=February 2014 |publisher=Sound Transit |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170223110424/http://www.wsdot.wa.gov/Partners/erp/Letters/Attach7%20Initial%20Light%20Rail%20Segment%20Before%20and%20After%20Study%20Final%20Report%20(2).pdf |archive-date=February 23, 2017 |url-status=live |via=[[Washington State Department of Transportation]]}}</ref>{{rp|6–7}}

===Stations===
{{further|List of Link light rail stations}}

Stations on the 1{{nbsp}}Line are spaced approximately {{convert|1|mi|km|1|spell=in}} apart in most areas and are built with {{convert|380|ft|m|-long|adj=mid}} platforms to accommodate four-car train sets.<ref name="BeforeAfter"/>{{rp|6}}<ref>{{cite news |last=Scigliano |first=Eric |date=October 26, 2016 |title=The South Seattle Neighborhood That Sound Transit Forgot |work=[[Seattle Weekly]] |url=http://www.seattleweekly.com/news/the-south-seattle-neighborhood-that-sound-transit-forgot/ |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110530/http://www.seattleweekly.com/news/the-south-seattle-neighborhood-that-sound-transit-forgot/ |archive-date=September 18, 2017}}</ref> Some stations are grade separated, with underground or elevated platforms connected to surface entrances by stairs, escalators, and elevators, while others were built at street level.<ref name="BeforeAfter"/>{{rp|6}} The line's stations include bus connections,<ref name="TDP">{{cite report |url=https://www.soundtransit.org/sites/default/files/transit-development-plan-2017-2022-and-2016-annual-report.pdf |title=Transit Development Plan 2017–2022 and 2016 Annual Report |date=August 2017 |publisher=Sound Transit |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170906041057/https://www.soundtransit.org/sites/default/files/transit-development-plan-2017-2022-and-2016-annual-report.pdf |archive-date=September 6, 2017 |url-status=dead}}</ref>{{rp|16}} [[ticket vending machine]]s, real-time [[Passenger information system|arrivals information]] signs, [[public art]], and bicycle parking.<ref name="Stations">{{cite web |title=Link light rail stations |url=https://www.soundtransit.org/schedules/light-rail/link-light-rail/stations |url-status=live |archive-url=https://web.archive.org/web/20170918110557/https://www.soundtransit.org/schedules/light-rail/link-light-rail/stations |archive-date=September 18, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref><ref>{{cite news |last=Gallagher |first=John |date=June 24, 2019 |title=Real-time information upgrades coming to Link light rail stations |work=The Platform |publisher=Sound Transit |url=https://www.soundtransit.org/blog/platform/real-time-information-upgrades-coming-to-link-light-rail-stations |access-date=June 27, 2019}}</ref> Stations are also designed with clear sight lines on platforms, emergency phones and lights, and are monitored with surveillance cameras.<ref>{{cite news |last=Green |first=Sara Jean |date=July 15, 2009 |title=Sound Transit pumps up light-rail security with lights, cameras, officers |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009472360_stsecurity15m.html |url-status=dead |access-date=March 4, 2018 |archive-url=https://web.archive.org/web/20180305072247/http://old.seattletimes.com/html/localnews/2009472360_stsecurity15m.html |archive-date=March 5, 2018}}</ref>

All stations are connected to local bus routes, including parallel [[King County Metro]], [[Community Transit]], and [[Sound Transit Express]] services that stop at multiple Link stations.<ref>{{cite web |title=Navigating service disruptions |url=https://www.soundtransit.org/ride-with-us/changes-affect-my-ride/navigating-service-disruptions |publisher=Sound Transit |accessdate=September 30, 2024}}</ref> Metro Flex, an on-demand [[Transportation network company|ride-hail]] shuttle service operated by King County Metro and [[Via (company)|Via]], launched in 2019 at five stations in the Rainier Valley and Tukwila. It accepted Metro fares and was subsidized by the Seattle city government.<ref>{{cite press release |date=April 16, 2019 |title=New on-demand shuttle service makes it more convenient than ever to take transit in southeast Seattle and Tukwila |url=https://www.kingcounty.gov/elected/executive/constantine/news/release/2019/April/16-transit-hubs-seattle-tukwila.aspx |publisher=King County Metro |access-date=April 21, 2019}}</ref> {{As of|2024}}, there are seven stations that have public park and ride facilities;<ref>{{cite news |last=Lindblom |first=Mike |date=July 5, 2023 |title=Your guide to getting around Seattle during All-Star Week by bus, rail, car, boat and more |url=https://www.seattletimes.com/seattle-news/transportation/your-guide-to-getting-around-seattle-during-all-star-week-by-bus-rail-car-boat-and-more/ |work=The Seattle Times |accessdate=July 5, 2023}}</ref><ref name="ST-LynnwoodPR">{{cite press release |date=August 30, 2024 |title=Light rail to Lynnwood opens |url=https://www.soundtransit.org/get-to-know-us/news-events/news-releases/light-rail-to-lynnwood-opens |publisher=Sound Transit |accessdate=August 30, 2024}}</ref> for other stations, Sound Transit and local governments encourage alternative means of transportation to and from stations, including bus riding, walking, or bicycling.<ref>{{cite news |last=Krishnan |first=Sonia |date=July 16, 2009 |title=Would-be light-rail riders bemoan lack of parking |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009479330_stparkingpic16txt1.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110637/http://old.seattletimes.com/html/localnews/2009479330_stparkingpic16txt1.html |archive-date=September 18, 2017}}</ref><ref>{{cite news |last=Chen |first=Natasha |date=March 29, 2016 |title=Parking problems intensify around light rail stations as more riders hop on |publisher=[[KIRO-TV|KIRO 7 News]] |url=http://www.kiro7.com/news/parking-problems-intensify-around-light-rail-stations-as-more-riders-hop-on/185910486 |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154325/http://www.kiro7.com/news/parking-problems-intensify-around-light-rail-stations-as-more-riders-hop-on/185910486 |archive-date=September 18, 2017}}</ref>

{{clear}}
{{sticky header}}
{| class="wikitable sortable sticky-header plainrowheaders"
|+ List of 1 Line stations
|-
! scope=col | Code<ref name="Schedule"/>
! scope=col | Station
! scope=col | Type<ref name="SafetyPlan"/>
! scope=col class="unsortable" | Image
! scope=col | Opened
! scope=col class="unsortable" | Connections and notes<ref name="TDP"/><ref name="Stations"/>
|-
| align=center | 40
! scope=row | {{stl|Sound Transit|Lynnwood City Center}}
| Elevated
| [[File:Lynnwood City Center Station opening day festival - 01.jpg|120x120px|center|alt=Western side of Lynnwood City Center Station on opening day with vendor booths and crowds in the foreground.]]
| {{dts|2024|08|30}}
| Park and ride: 1,670 stalls<ref name="ST-LynnwoodPR"/>
|-
| align=center | 41
! scope=row | {{stn|Mountlake Terrace}}
| Elevated
| [[File:Mountlake Terrace Station opening day festival - 01.jpg|120x120px|center|alt=Eastern side of Mountlake Terrace Station on opening day with booths in the foreground.]]
| {{dts|2024|08|30}}
| Park and ride: 890 stalls<ref name="ST-LynnwoodPR"/>
|-
| align=center | 42
! scope=row | {{stn|Shoreline North/185th}}
| At-grade
| [[File:Shoreline North 185th Station on opening day.jpg|120x120px|center|alt=Shoreline North/185th Station from the south side on opening day]]
| {{dts|2024|08|30}}
| Park and ride: 500 stalls<ref name="ST-LynnwoodPR"/>
|-
| align=center | 43
! scope=row | {{stn|Shoreline South/148th}}
| Elevated
| [[File:Shoreline South 148th Station view from parking garage - 01.jpg|120x120px|center|alt=Shoreline South/148th Station platforms viewed from the elevated parking garage]]
| {{dts|2024|08|30}}
| Park and ride: 500 stalls<ref name="ST-LynnwoodPR"/>
|-
| align=center | 45
! scope=row | {{stn|Northgate||Sound Transit}}
| Elevated
| [[File:Northgate Station on opening day, seen from the bridge - 03.jpg|120x120px|center|alt=Western side of Northgate station on opening day]]
| {{dts|2021|10|02}}
| Park and ride: 1,525 stalls<ref>{{cite news |last1=Lindblom |first1=Mike |last2=Baruchman |first2=Michelle |date=September 26, 2021 |title=Fast facts about light-rail expansion to U District, Roosevelt, Northgate |url=https://www.seattletimes.com/seattle-news/transportation/fast-facts-about-northgate-light-rail-before-it-opens-saturday/ |work=The Seattle Times |access-date=October 2, 2021}}</ref>
|-
| align=center | 46
! scope=row | {{stn|Roosevelt||Sound Transit}}
| Underground
| [[File:Roosevelt Station - north entrance bike area on opening day.jpg|120x120px|center|alt=Entrance to Roosevelt station]]
| {{dts|2021|10|02}}
|
|-
| align=center | 47
! scope=row | {{stn|U District}}
| Underground
| [[File:U District Station - platform escalators on media preview day - 02.jpg|120x120px|center|alt=Platform level at U District station]]
| {{dts|2021|10|02}}
|
|-
| align=center | 48
! scope=row | {{stn|University of Washington}}
| Underground
| [[File:University of Washington Station entrance, Aug 2016 (29979336625).jpg|120x120px|center|alt=Entrance to University of Washington station]]
| {{dts|2016|03|19}}
|
|-
| align=center | 49
! scope=row | {{stn|Capitol Hill}}
| Underground
| [[File:Capitol Hill Station platform on opening day, March 19, 2016 - 01.jpg|120x120px|center|alt=Platform at Capitol Hill station]]
| {{dts|2016|03|19}}
| Connects with [[First Hill Streetcar]]
|-
| align=center | 50
! scope=row | {{stn|Westlake||Sound Transit}}
| Underground
| [[File:Link Light Rail at Westlake Station (10873527453).jpg|120x120px|center|alt=Light rail train arriving at Westlake station's platform]]
| {{dts|2009|07|18}}{{refn|group=n|name=DSTT|Stations in the [[Downtown Seattle Transit Tunnel]] originally opened as bus-only facilities on September 15, 1990, with light rail service commencing on July 18, 2009.<ref>{{cite book |last=Viriyincy |first=Oran |year=2013 |title=Back To The Future: A History of Transit Planning in the Puget Sound Region |chapter=Chapter 3: Seattle Bus Tunnel |page=48 |publisher=[[University of Washington College of Built Environments]] |location=Seattle |isbn=978-1304103390 |oclc=961186618 |url=https://books.google.com/books?id=4--gBQAAQBAJ |via=Google Books |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20180119063248/https://books.google.com/books?id=4--gBQAAQBAJ |archive-date=January 19, 2018}}</ref>}}
| Connects with [[Seattle Center Monorail]] and [[South Lake Union Streetcar]]
|-
| align=center | 51
! scope=row | {{stn|Symphony||Sound Transit}}{{refn|group=n|name=Symphony|Formerly named University Street station until August 30, 2024.<ref name="Times-Symphony"/>}}
| Underground
| [[File:Metro bus and Link light rail passing at University Street Station (2010).jpg|120x120px|center|alt=Metro bus and light rail train at Symphony station]]
| {{dts|2009|07|18}}{{refn|group=n|name=DSTT}}
|
|-
| align=center | 52
! scope=row | {{stn|Pioneer Square}}
| Underground
| [[File:Seattle - Pioneer Square Station July 2009.jpg|120x120px|center|alt=Light rail train at Pioneer Square station]]
| {{dts|2009|07|18}}{{refn|group=n|name=DSTT}}
| Connects with [[Washington State Ferries]], [[King County Water Taxi]], and [[Kitsap Fast Ferries]]
|-
| align=center | 53
! scope=row | {{stn|International District/Chinatown}}
| Underground
| [[File:Both levels of International District-Chinatown station (2010).jpg|120x120px|center|alt=Light rail train and bus at International District/Chinatown station]]
| {{dts|2009|07|18}}{{refn|group=n|name=DSTT}}
| Connects with [[Amtrak]], [[Sounder commuter rail]], and [[First Hill Streetcar]]
|-
| align=center | 54
! scope=row | {{stn|Stadium||Sound Transit}}
| At-grade
| [[File:Stadium Station ORCA readers.jpg|120x120px|center|alt=Entrance to Stadium station]]
| {{dts|2009|07|18}}
| Connects with [[Greyhound Lines|Greyhound]]
|-
| align=center | 55
! scope=row | {{stn|SODO||Sound Transit}}
| At-grade
| [[File:Link Series 1 LRV 155 at SODO Station, Seattle.jpg|120x120px|center|alt=Light rail train at SODO station]]
| {{dts|2009|07|18}}
|
|-
| align=center | 56
! scope=row | {{stn|Beacon Hill||Sound Transit}}
| Underground
| [[File:Beacon Hill Light Rail Station two.JPG|120x120px|center|alt=Entrance and headhouse at Beacon Hill station]]
| {{dts|2009|07|18}}
|
|-
| align=center | 57
! scope=row | {{stn|Mount Baker}}
| Elevated
| [[File:Mount Baker Station from MLK Way (20400419804).jpg|120x120px|center|alt=Mount Baker station, viewed from across the street]]
| {{dts|2009|07|18}}
|
|-
| align=center | 58
! scope=row | {{stn|Columbia City}}
| At-grade
| [[File:Columbia City station southbound platform, Dec. 2017.jpg|120x120px|center|alt=Platforms at Columbia City station]]
| {{dts|2009|07|18}}
|
|-
| align=center | 60
! scope=row | {{stn|Othello}}
| At-grade
| [[File:Othello-New Holly Station SEA Link (4575069147).jpg|120x120px|center|alt=Platform at Othello station]]
| {{dts|2009|07|18}}
|
|-
| align=center | 61
! scope=row | {{stn|Rainier Beach}}
| At-grade
| [[File:Rainier Beach Station (Sound Transit Central Link).jpg|120x120px|center|alt=Light rail train at Rainier Beach station]]
| {{dts|2009|07|18}}
|
|-
| align=center | 63
! scope=row | {{stn|Tukwila International Boulevard}}
| Elevated
| [[File:Tukwila Int'l Blvd Station - 01.jpg|120x120px|center|alt=Park and ride at Tukwila International Boulevard station]]
| {{dts|2009|07|18}}
| Park and ride: 662 stalls
|-
| align=center | 64
! scope=row | {{stn|SeaTac/Airport}}
| Elevated
| [[File:SeaTac light rail station from airport parking garage (2010).jpg|120x120px|center|alt=Platform and mezzanine at SeaTac/ Airport station]]
| {{dts|2009|12|19}}
| Connects with [[Seattle–Tacoma International Airport]]
|-
| align=center | 65
! scope=row | {{stn|Angle Lake}}
| Elevated
| [[File:Angle Lake Station on opening day, September 24, 2016.jpg|120x120px|center|alt=Platform at Angle Lake station]]
| {{dts|2016|09|24}}
| Park and ride: 1,120 stalls
|}

====Notes====
{{reflist|group=n}}

==Service==

1{{nbsp}}Line trains run 20 hours per day from Monday to Saturday, from 5:00&nbsp;am to 1:00&nbsp;am, and 18 hours on Sundays and [[Federal holidays in the United States|federal holidays]], from 6:00&nbsp;am to midnight.<ref name="Schedule">{{cite web |date=August 2024 |title=Link 1 Line: Lynnwood City Center – Angle Lake schedule |url=https://www.soundtransit.org/sites/default/files/documents/schedule-link-1-line.pdf |publisher=Sound Transit |accessdate=August 30, 2024}}</ref><ref name="ST-2002EA">{{cite book |url=https://books.google.com/books?id=7y43AQAAMAAJ |title=Central Link Light Rail Transit Project: Initial Segment Environmental Assessment |date=February 2002 |publisher=Sound Transit |page=45 |chapter=Chapter 4: Financial Analysis |oclc=48937173 |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20180119063248/https://books.google.com/books?id=7y43AQAAMAAJ |archive-date=January 19, 2018 |url-status=live |via=[[Google Books]]}}</ref> Trains operate most frequently during weekday [[peak period]]s, running every eight minutes from 6:00&nbsp;am to 9:30&nbsp;am and from 3:00&nbsp;pm to 6:30&nbsp;pm. Trains run every 10 minutes during midday and evening hours on weekdays and all day on weekends. Train frequency is reduced to every 15 minutes during the early morning and late night hours of all days.<ref name="Schedule"/>

End-to-end travel from Lynnwood to Angle Lake stations takes 73&nbsp;minutes, while trips between SeaTac/Airport station and Downtown Seattle take 38 minutes.<ref name="Schedule"/> The SeaTac–Westlake corridor was formerly served by King County Metro bus route 194, which took 32 minutes to travel between the two areas, and used bus stops that were closer to the terminal. The bus route ran at less frequent intervals, was subject to traffic delays, and had shorter hours of operation.<ref>{{cite news |last=Lindblom |first=Mike |date=November 14, 2009 |title=Light rail to airport to begin Dec. 19 |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2010272103_airportlink14m.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110609/http://old.seattletimes.com/html/localnews/2010272103_airportlink14m.html |archive-date=September 18, 2017}}</ref><ref>{{cite web |date=January 10, 2009 |title=Proposed Service Change: Downtown Seattle&nbsp;– Sea-Tac International Airport |url=http://transit.metrokc.gov/up/sc/plans/2009/012009-sesea-dts-sta.html |publisher=King County Metro |url-status=dead |archive-url=https://web.archive.org/web/20090511192443/http://transit.metrokc.gov/up/sc/plans/2009/012009-sesea-dts-sta.html |archive-date=May 11, 2009 |access-date=September 17, 2017}}</ref> The final four northbound trips during late night service terminate at [[Beacon Hill station (Sound Transit)|Beacon Hill station]] instead of continuing through Downtown Seattle to allow for overnight maintenance to begin earlier on some sections; prior to 2024, these trains terminated at Stadium station.<ref>{{cite news |last=Alquist |first=Nic |date=March 8, 2024 |title=Late night 1 Line service to see changes starting March 30 |url=https://www.soundtransit.org/blog/platform/late-night-1-line-service-to-see-changes-starting-march-30 |work=The Platform |publisher=Sound Transit |accessdate=May 3, 2024}}</ref>

===Ridership===
{| class="wikitable sortable floatright" style="border-spacing: 1px; text-align:center; font-size:95%;"
|+ Annual 1 Line ridership
|- 
! style="border-bottom:1px solid black"| Year !! style="border-bottom:1px solid black"| Ridership !!style="border-bottom:1px solid black"|  {{abbr|%±|Percent change}}
|- 
|2009
|{{formatnum:2501211}}
|&nbsp;—
|-
|2010
|{{formatnum:6989504}}
| {{#expr: ((6989504-2501211) / 2501211)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place. Will show negative if necessary -->
|-
|2011
|{{formatnum:7812433}}
| {{#expr: ((7812433-6989504) / 6989504)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2012
|{{formatnum:8699821}}
| {{#expr: ((8699821-7812433) / 7812433)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2013
|{{formatnum:9681432}}
| {{#expr: ((9681432-8699821) / 8699821)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2014
|{{formatnum:10937883}}
| {{#expr: ((10937883-9681432) / 9681432)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2015
|{{formatnum:11530411}}
| {{#expr: ((11530411-10937883) / 10937883)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2016
|{{formatnum:19121621}}
| {{#expr: ((19121621-11530411) / 11530411)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2017
|{{formatnum:23186633}}
| {{#expr: ((23186633-19121621) / 19121621)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2018
|{{formatnum:24416411}}
| {{#expr: ((24416411-23186633) / 23186633)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2019
|{{formatnum:25075922}}
| {{#expr: ((25075922-24416411) / 24416411)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2020
|{{formatnum:9660736}}
| {{#expr: ((9660736-25075922) / 25075922)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2021
|{{formatnum:11512650}}
| {{#expr: ((11512650-9660736) / 9660736)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2022
|{{formatnum:23706210}}
| {{#expr: ((23706210-11512650) / 11512650)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|-
|2023
|{{formatnum:26883140}}
| {{#expr: ((26883140-23706210) / 23706210)*100 round 1}}% <!-- This year's ridership minus last year's ridership divided by last year's ridership (times 100 and adding a '%', rounded to 1 decimal place). Will show negative if necessary -->
|- class="sortbottom"
| colspan="3" style="border-top:1px solid black; font-size:85%; text-align:left" |Source: Sound Transit<ref name="Ridership"/><ref name="ridershipreports">{{cite web |title=Quarterly Ridership Report |url=http://www.soundtransit.org/Ridership |publisher=Sound Transit |access-date=March 6, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170318151654/http://www.soundtransit.org/ridership |archive-date=March 18, 2017}}</ref>
|}
1{{nbsp}}Line trains carried over 26.88&nbsp;million total passengers in 2023, averaging 78,944 riders on weekdays.<ref name="Ridership">{{cite web |title=System performance tracker: Link Ridership |url=https://www.soundtransit.org/ride-with-us/system-performance-tracker/ridership |publisher=Sound Transit |accessdate=January 31, 2024}}</ref> Ridership is measured by on-board infrared passenger counters that automatically record the number of people entering and leaving the train.<ref name="Times-12K"/><ref>{{cite news |date=February 10, 2015 |title=Transit technology works for you |publisher=Sound Transit |url=https://www.soundtransit.org/blog/platform/transit-technology-works-for-you |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918112315/https://www.soundtransit.org/blog/platform/transit-technology-works-for-you |archive-date=September 18, 2017}}</ref> {{As of|2022}}, approximately 32&nbsp;percent of Series 1 vehicles have automatic passenger counters, while all Series 2 vehicles were installed with them.<ref name="ST-TDP">{{cite web |date=August 25, 2022 |title=Transit Development Plan 2022–2027 and 2021 Annual Report |url=https://www.soundtransit.org/sites/default/files/documents/sound-transit-tdp-2022-2027-and-2021-annual-report-20220825.pdf |accessdate=November 17, 2022 |publisher=Sound Transit |pages=17–19}}</ref>

Ridership on the 1{{nbsp}}Line has risen significantly from the beginning of service in 2009, when it averaged 15,500 per weekday.<ref>{{cite report |url=https://www.soundtransit.org/sites/default/files/documents/pdf/newsroom/2010_tdp_2009annualrpt.pdf |title=Transit Development Plan 2010–2015 and 2009 Annual Report |date=March 18, 2010 |publisher=Sound Transit |page=16 |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110630/https://www.soundtransit.org/sites/default/files/documents/pdf/newsroom/2010_tdp_2009annualrpt.pdf |archive-date=September 18, 2017 |url-status=dead}}</ref> In 2010, ridership fell below projected levels due to an [[Great Recession in the United States|economic downturn]], with only 21,611 daily riders on the line.<ref>{{cite news |last=Lindblom |first=Mike |date=March 3, 2011 |title=Sound Transit ridership falls short of its goals |page=B1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2014381404_soundtransit03m.html |url-status=dead |access-date=August 25, 2016 |archive-url=https://web.archive.org/web/20160825225751/http://old.seattletimes.com/html/localnews/2014381404_soundtransit03m.html |archive-date=August 25, 2016}}</ref> Ridership increased significantly in the following years, surpassing 25,000 daily riders in 2012,<ref>{{cite web |year=2013 |title=Fourth Quarter 2012 Service Delivery Quarterly Performance Report |url=https://www.soundtransit.org/sites/default/files/documents/pdf/rider_news/ridership/2012q4_quarterlyservicedeliveryperformancereport.pdf |url-status=live |archive-url=https://web.archive.org/web/20160313073834/http://www.soundtransit.org/sites/default/files/documents/pdf/rider_news/ridership/2012q4_quarterlyservicedeliveryperformancereport.pdf |archive-date=March 13, 2016 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> 30,000 in 2014,<ref>{{cite web |date=February 26, 2015 |title=Fourth Quarter 2014 Service Delivery Quarterly Performance Report |url=https://www.soundtransit.org/sites/default/files/documents/pdf/rider_news/ridership/2012q4_quarterlyservicedeliveryperformancereport.pdf |url-status=live |archive-url=https://web.archive.org/web/20160313073834/http://www.soundtransit.org/sites/default/files/documents/pdf/rider_news/ridership/2012q4_quarterlyservicedeliveryperformancereport.pdf |archive-date=March 13, 2016 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> and 35,000 in 2015.<ref>{{cite web |date=February 25, 2016 |title=Fourth Quarter 2015 Service Delivery Quarterly Performance Report |url=https://www.soundtransit.org/sites/default/files/q4_2015_rpt_service_delivery.pdf |url-status=live |archive-url=https://web.archive.org/web/20160418082216/http://www.soundtransit.org/sites/default/files/q4_2015_rpt_service_delivery.pdf |archive-date=April 18, 2016 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref>

The opening of the University Link extension in March 2016 increased daily ridership by 66 percent in its first month of operation,<ref name="Ridership-Apr16">{{cite web |date=April 20, 2016 |title=University Link ridership sprints out of the starting gates |url=http://www.soundtransit.org/Rider-Community/Rider-news/university-link-ridership-sprints-out-starting-gates |url-status=dead |archive-url=https://web.archive.org/web/20160825231339/http://www.soundtransit.org/Rider-Community/Rider-news/university-link-ridership-sprints-out-starting-gates |archive-date=August 25, 2016 |access-date=August 25, 2016 |publisher=Sound Transit}}</ref> and averaged 66,203 daily riders during the last quarter of the year.<ref>{{cite web |date=February 17, 2017 |title=Fourth Quarter 2016 Service Delivery Quarterly Performance Report |url=https://www.soundtransit.org/sites/default/files/2016-Q4%20Service%20Delivery%20Performance%20Report.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170218064224/http://www.soundtransit.org/sites/default/files/2016-Q4%20Service%20Delivery%20Performance%20Report.pdf |archive-date=February 18, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> A single-day ridership record of 82,361 estimated boardings was set on April 8, 2016,<ref>{{cite press release |date=August 25, 2016 |title=New light rail riders drive record-breaking second quarter ridership |url=http://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/new-light-rail-riders-drive-record-breaking-second |publisher=Sound Transit |access-date=August 25, 2016 |url-status=live |archive-url=https://web.archive.org/web/20160825231300/http://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/new-light-rail-riders-drive-record-breaking-second |archive-date=August 25, 2016}}</ref> credited to a [[Seattle Mariners]] home opener and the [[Emerald City Comic Con]].<ref name="Ridership-Apr16"/> The record was surpassed five months later on September 30, estimated at 101,000 riders, due in part to home games for the [[Washington Huskies football]] team and Seattle Mariners.<ref>{{cite news |last=Lindblom |first=Mike |date=October 7, 2016 |title=UW-Stanford game helps break light-rail record of more than 100,000 riders |page=B1 |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/uw-stanford-game-helps-break-light-rail-record-with-more-than-100000-riders/ |url-status=live |url-access=limited |access-date=October 6, 2016 |archive-url=https://web.archive.org/web/20161007025259/http://www.seattletimes.com/seattle-news/transportation/uw-stanford-game-helps-break-light-rail-record-with-more-than-100000-riders/ |archive-date=October 7, 2016}}</ref>

Ridership fell to 9.7&nbsp;million total passengers in 2020, a decline of 61&nbsp;percent from 2019, due to the [[COVID-19 pandemic]] and other service reductions.<ref name="Ridership-2020">{{cite web |date=February 25, 2021 |title=Q4 2020 Service Delivery Quarterly Performance Report |url=https://www.soundtransit.org/sites/default/files/documents/2020-q4-service-delivery-performance-report.pdf |publisher=Sound Transit |access-date=March 4, 2021}}</ref> Link ridership grew following the 2021 opening of the Northgate Link Extension and reopening of offices, which allowed it to exceed pre-pandemic levels.<ref>{{cite news |last=Kroman |first=David |date=January 1, 2023 |title=Sounder trains' future in limbo as riders are slow to return |url=https://www.seattletimes.com/seattle-news/transportation/sounder-trains-future-in-limbo-as-ridership-is-slow-to-return/ |work=The Seattle Times |accessdate=August 11, 2023}}</ref> The line set a single-day record of 115,600&nbsp;boardings on July 11, 2023, during the [[2023 Major League Baseball All-Star Game|Major League Baseball All-Star Game]] at [[T-Mobile Park]]. This record was surpassed twice by the end of the month due to several simultaneous weekend events, including [[Taylor Swift]]'s [[The Eras Tour]] concerts at [[Lumen Field]], Mariners games at T-Mobile Park, and the [[Capitol Hill Block Party]]. A new record of 136,800&nbsp;boardings was set on July 23 and became the 12th day in July 2023 with more than 100,000&nbsp;boardings.<ref>{{cite news |last=Lindblom |first=Mike |date=August 11, 2023 |title=Seattle light rail sets ridership records amid big events, games |url=https://www.seattletimes.com/seattle-news/transportation/seattle-light-rail-sets-ridership-records-amid-big-events-games/ |work=The Seattle Times |accessdate=August 11, 2023}}</ref>
<!--{{Graph:Chart|width=300|height=200|colors=#{{rcr|Sound Transit|1 Line}}|type=rect|xAxisAngle=-40|xAxisTitle=Year|x=2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022|yAxisTitle=Ridership|yType=integer|yGrid=|yAxisFormat=s|y=2501211, 6989504, 7812433, 8699821, 9681432, 10937883, 11530411, 19121621, 23186633, 24416411, 25075922, 9660736, 11512650, 23579000}}-->
===Fares===

The 1{{nbsp}}Line uses a [[proof-of-payment]] system, requiring valid payment before boarding and lacking a [[turnstile]] barrier at stations. Fares can be purchased as paper tickets at [[ticket vending machine]]s at stations,<ref>{{cite web |date=June 23, 2017 |title=Ticket Vending Machines |url=https://www.soundtransit.org/sites/default/files/orca_tvm_list.pdf |url-status=live |archive-url=https://web.archive.org/web/20170706105737/https://www.soundtransit.org/sites/default/files/orca_tvm_list.pdf |archive-date=July 6, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> credit or passes loaded on an [[ORCA card]], or through a [[mobile ticketing]] app.<ref>{{cite web |title=Transit GO Ticket |url=http://kingcounty.gov/depts/transportation/metro/fares-orca/transit-go-ticket.aspx |url-status=live |archive-url=https://web.archive.org/web/20170918154233/http://kingcounty.gov/depts/transportation/metro/fares-orca/transit-go-ticket.aspx |archive-date=September 18, 2017 |access-date=September 17, 2017 |publisher=King County Metro}}</ref> Fare ambassadors check for valid fares while aboard trains or in the fare-paid zone of stations;<ref>{{cite news |last=Gray |first=Bruce |date=November 14, 2017 |title=Why doesn't Link light rail use turnstiles? |work=The Platform |publisher=Sound Transit |url=https://www.soundtransit.org/blog/platform/why-doesnt-link-light-rail-use-turnstiles |url-status=live |access-date=February 21, 2018 |archive-url=https://web.archive.org/web/20180222083108/https://www.soundtransit.org/blog/platform/why-doesnt-link-light-rail-use-turnstiles |archive-date=February 22, 2018}}</ref> passengers who do not present a valid ticket or validated ORCA card are offered educational materials and warnings.<ref>{{cite news |last=Kroman |first=David |date=January 27, 2022 |title=Sound Transit fares on 'unsustainable' trajectory, CEO warns |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/with-fares-depressed-sound-transit-grapples-with-financially-unsustainable-trajectory/ |accessdate=January 29, 2022}}</ref> Until 2021, fare inspectors and transit police officers checked fares and issued warnings or a $124 [[Traffic citation|citation]] to passengers who did not present a valid form of payment.<ref>{{cite news |last=Lindblom |first=Mike |date=July 8, 2014 |title=Shooting brings attention to light rail's fare inspection force |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2024016225_fareinspectorsxml.html |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154233/http://old.seattletimes.com/html/localnews/2024016225_fareinspectorsxml.html |archive-date=September 18, 2017}}</ref><ref>{{cite news |last=Lindblom |first=Mike |date=August 12, 2009 |title=Link's ticket system confounds light-rail riders |page=A1 |work=The Seattle Times |url=http://old.seattletimes.com/html/localnews/2009642729_stfares12m.html |url-status=dead |access-date=February 21, 2018 |archive-url=https://web.archive.org/web/20180222083108/http://old.seattletimes.com/html/localnews/2009642729_stfares12m.html |archive-date=February 22, 2018}}</ref> Following the dismissal of fare inspectors, an estimated 42&nbsp;percent of passengers in January 2022 did not pay their fare.<ref>{{cite news |last=Kroman |first=David |date=April 28, 2022 |title=Sound Transit eases fare enforcement amid equity concerns |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/sound-transit-eases-fare-enforcement-amid-equity-concerns/ |accessdate=September 17, 2022}}</ref> A new program led by fare ambassadors was approved in September 2022, enacting a multi-step system with monetary penalties beginning with the third violation and a $124 infraction for a fifth violation.<ref>{{cite news |last=Lindblom |first=Mike |date=September 2, 2022 |title=Sound Transit goes all-in on a gentler kind of fare enforcement |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/sound-transit-goes-all-in-on-a-gentler-kind-of-fare-enforcement/ |accessdate=September 17, 2022}}</ref>

Fares are a flat rate of $3 for adults, $1 for passengers eligible for reduced fares, and free for people 18 years old or younger.<ref>{{cite news |last=Lindblom |first=Mike |date=August 30, 2024 |title=Light rail to Lynnwood starts today; so do flat fares, systemwide |url=https://www.seattletimes.com/seattle-news/transportation/light-rail-to-lynnwood-starts-today-so-do-flat-fares-systemwide/ |work=The Seattle Times |accessdate=August 30, 2024}}</ref> Until 2024, the fares were calculated based on distance traveled and ranged from $2.25 to $3.50 for adults.<ref>{{cite news |last=Lindblom |first=Mike |date=December 15, 2023 |title=Sound Transit light rail to cost $3 a ride — for trips near or far |url=https://www.seattletimes.com/seattle-news/transportation/sound-transit-light-rail-to-cost-3-a-ride-for-trips-near-or-far/ |work=The Seattle Times |accessdate=August 30, 2024}}</ref> ORCA card users were required to tap a reader before and after riding a train to calculate the fare.<ref>{{cite web |last=Johnson |first=Matthew |date=September 24, 2015 |title=Q: Why do I need to tap on and tap off my ORCA card? |url=https://www.soundtransit.org/blog/platform/q-why-do-i-need-tap-and-tap-my-orca-card |url-status=live |archive-url=https://web.archive.org/web/20170918110655/https://www.soundtransit.org/blog/platform/q-why-do-i-need-tap-and-tap-my-orca-card |archive-date=September 18, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> Reduced fares are available to elderly passengers, persons with disabilities, and low-income passengers enrolled in ORCA Lift.<ref>{{cite web |title=How to pay |url=https://www.soundtransit.org/ride-with-us/how-to-pay/fares |access-date=October 31, 2022 |publisher=Sound Transit}}</ref><ref>{{cite web |title=ORCA Lift |url=http://kingcounty.gov/depts/transportation/metro/fares-orca/orca-cards/lift.aspx |url-status=live |archive-url=https://web.archive.org/web/20170930212912/http://kingcounty.gov/depts/transportation/metro/fares-orca/orca-cards/lift.aspx |archive-date=September 30, 2017 |access-date=September 17, 2017 |publisher=King County Metro}}</ref> Transfers from other modes, including buses, [[King County Water Taxi|water taxis]], and [[Seattle Streetcar|streetcars]], are only accepted using ORCA cards.<ref>{{cite news |last=Lee |first=Jessica |date=May 22, 2017 |title=From ORCA cards to bus-driver behavior: questions and answers |page=B1 |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/from-orca-cards-to-bus-driver-behavior-you-have-questions-and-we-have-answers/ |url-status=live |url-access=limited |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110634/http://www.seattletimes.com/seattle-news/transportation/from-orca-cards-to-bus-driver-behavior-you-have-questions-and-we-have-answers/ |archive-date=September 18, 2017}}</ref> Since September 2022, fares for passengers under the age of 19 have been free as part of a statewide transit grant.<ref>{{cite news |last=Kroman |first=David |date=September 1, 2022 |title=Free transit starts today for most youths across WA |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/free-transit-starts-today-for-most-youths-across-wa/ |accessdate=October 31, 2022}}</ref>

==Rolling stock and equipment==
{{multiple image
| align             = right
| direction         = vertical
| width             = 250
| caption_align     = left
| image1            = Central Link Light Rail interior with cab door window (5534256558).jpg
| caption1          = Interior of a [[Kinki Sharyo|Kinkisharyo]]-[[Mitsui & Co.|Mitsui]] light rail vehicle, used by Sound Transit on the 1{{nbsp}}Line
| alt1              = Inside an empty train with large windows, several seats arranged parallel and perpendicularly, metal handlebars, and black hand-holds. The far section of the train with additional seating is lifted up and has a short stairway.
| image2            = Sound Transit Type 2 S70 LRV number 202 at SODO OMF.jpg
| caption2          = Exterior of a [[Siemens S700 and S70|Siemens S700]]{{efn|name=retroactive-rebrand}} light rail vehicle, a type that entered service on Link in 2021
| alt2              = Exterior view of a train parked in a garage.
}}

The original "Series&nbsp;1" fleet used on the 1{{nbsp}}Line consisted of 62 [[Low-floor tram|low-floor]] light rail vehicles manufactured in Japan by [[Kinki Sharyo|Kinkisharyo]].<ref name="TDP"/>{{rp|8}} The Kinkisharyo vehicles, built through a [[joint venture]] with [[Mitsui & Co.]],<ref name="Times-2003LRV">{{cite news |last=Pryne |first=Eric |date=November 25, 2003 |title=Sound Transit picks Japanese firm to build train cars for light-rail line |page=B3 |work=The Seattle Times |url=http://community.seattletimes.nwsource.com/archive/?date=20031125&slug=sound25m |url-status=live |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918154253/http://community.seattletimes.nwsource.com/archive/?date=20031125&slug=sound25m |archive-date=September 18, 2017}}</ref> have 74 seats and can carry 194 seated and standing passengers at standard capacity; a maximum "[[crush load]]" of 252 passengers per car can be carried by Link trains for short distances.<ref name="Times-2016Capacity">{{cite news |last=Lindblom |first=Mike |date=August 8, 2016 |title=Sound Transit keeping close eye on crowded light-rail trains |page=A7 |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/sound-transit-keeping-close-eye-on-crowded-light-rail-trains/ |url-status=live |url-access=limited |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170918110601/http://www.seattletimes.com/seattle-news/transportation/sound-transit-keeping-close-eye-on-crowded-light-rail-trains/ |archive-date=September 18, 2017}}</ref> Individual railcars are {{convert|95|ft|m|1}} long and {{convert|8.7|ft|m|1}} wide, sporting dual cabs that allow cars to travel in either direction.<ref name="Kinkisharyo">{{cite web |date=August 2015 |title=Technical Data: Seattle, WA&nbsp;– Sound Transit |url=http://www.kinkisharyo.com/main/wp-content/uploads/2015/08/ST.pdf |url-status=live |archive-url=https://web.archive.org/web/20170906042306/http://www.kinkisharyo.com/main/wp-content/uploads/2015/08/ST.pdf |archive-date=September 6, 2017 |access-date=September 17, 2017 |publisher=[[Kinki Sharyo|Kinkisharyo International]]}}</ref> The interior is 70 percent low-floor, while the remaining 30 percent is raised above the floor and accessed via stairs. Railcars include four doors on each side, [[Folding seat|fold-up seating]] areas for wheelchairs, and two bicycle hooks above [[luggage]] storage areas.<ref name="OpsPlan">{{cite report |url=http://www.globaltelematics.com/pitf/SoundTransitCentralLinkOpsPlan.7.29.08.pdf |title=Central Link Operations Plan&nbsp;– Westlake to SeaTac/Airport |date=July 29, 2008 |publisher=Sound Transit |pages=18–21 |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20150924022530/http://www.globaltelematics.com/pitf/SoundTransitCentralLinkOpsPlan.7.29.08.pdf |archive-date=September 24, 2015 |url-status=live}}</ref><ref>{{cite web |date=June 2017 |title=Bicycle Riders Guide |url=https://www.soundtransit.org/sites/default/files/bicycle-riders-guide.pdf |url-status=live |archive-url=https://web.archive.org/web/20170918110708/https://www.soundtransit.org/sites/default/files/bicycle-riders-guide.pdf |archive-date=September 18, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> 1{{nbsp}}Line trains are typically arranged into three-car and four-car sets,<ref>{{cite news |last=Lindblom |first=Mike |date=August 29, 2024 |title=Light rail for beginners: How to ride the new Lynnwood extension |url=https://www.seattletimes.com/seattle-news/transportation/light-rail-for-beginners-how-to-ride-the-new-lynnwood-extension/ |work=The Seattle Times |accessdate=September 26, 2024}}</ref> but until 2021 all trains were two or three cars long.<ref name="Times-2016Capacity"/><ref>{{cite press release |date=October 20, 2005 |title=Four new light rail cars proposed for Sound Transit's Airport Link extension |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Four-new-light-rail-cars-proposed-for-Sound-Transits-Airport-Link-extension |publisher=Sound Transit |access-date=August 9, 2016 |url-status=live |archive-url=https://web.archive.org/web/20160816191904/http://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Four-new-light-rail-cars-proposed-for-Sound-Transits-Airport-Link-extension |archive-date=August 16, 2016}}</ref> The trains have a top speed of {{convert|58|mph}}, but typically operate at {{convert|35|mph|kph|abbr=on}} on surface sections and {{convert|55|mph|kph|abbr=on}} on elevated and tunneled sections.<ref name="Kinkisharyo"/><ref>{{cite web |date=July 10, 2009 |title=The Light-Rail Train |url=http://seattletimes.nwsource.com/ABPub/2009/07/10/2009450350.pdf |url-status=live |archive-url=https://web.archive.org/web/20170826104804/http://seattletimes.nwsource.com/ABPub/2009/07/10/2009450350.pdf |archive-date=August 26, 2017 |access-date=September 17, 2017 |publisher=The Seattle Times}}</ref> Link uses a form of [[positive train control]] to prevent trains from exceeding the set speed limit for a given area.<ref>{{cite news |last=Lindblom |first=Mike |date=May 27, 2015 |title=State finally getting satellite-based train controls, 20 years after fatal crash |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/tracking-washington-states-train-safety/ |url-access=limited |access-date=January 30, 2019}}</ref>

Trains are supplied electricity through an [[Overhead line|overhead catenary]] that is energized at {{1,500 V DC}} and converted to [[Three-phase electric power|three-phase]] [[alternating current]] through on-board [[inverter]]s.<ref name="OpsPlan"/> While other North American light rail systems use {{750 V DC}} technology, Sound Transit chose to use 1,500 V DC to reduce the number of [[electrical substation]]s, which are spaced approximately {{convert|1|mi|km|1|spell=in}} apart.<ref name="OpsPlan"/><ref>{{cite journal |last=Middleton |first=William D. |author-link=William D. Middleton |date=April 1, 2006 |title=Sound Transit builds for LRT: Projected growth over the next 25 years is driving the Seattle region's rapid push to expand light rail. |url=http://www.railwayage.com/B/feature2.html |url-status=dead |journal=[[Railway Age]] |location=Chicago, Illinois |publisher=[[Simmons-Boardman Publishing]] |pages=43–45 |issn=0033-8826 |oclc=1586268 |archive-url=https://web.archive.org/web/20060502105012/http://www.railwayage.com/B/feature2.html |archive-date=May 2, 2006 |access-date=September 17, 2017}}</ref> Sound Transit placed its initial order of 31 light rail vehicles in 2003, and added four more vehicles in 2005 for the extension to SeaTac/Airport station.<ref name="Times-2003LRV"/><ref>{{cite web |date=December 8, 2005 |title=Sound Transit Motion No. M2005-117 |url=https://www.soundtransit.org/sites/default/files/documents/pdf/about/board/motions/2005/motionm2005-117sr.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170918110522/https://www.soundtransit.org/sites/default/files/documents/pdf/about/board/motions/2005/motionm2005-117sr.pdf |archive-date=September 18, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> The cars were assembled in Everett, to comply with [[Buy America]] requirements,<ref>{{cite news |last=Velush |first=Lukas |date=May 22, 2007 |title=Rail cars finished in Everett |work=[[The Everett Herald]] |url=http://www.heraldnet.com/stories/07/05/22/100loc_b1rail001.cfm |url-status=dead |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20070524112643/http://www.heraldnet.com/stories/07/05/22/100loc_b1rail001.cfm |archive-date=May 24, 2007}}</ref> and delivered from 2006 to 2008.<ref name="ST-2014Kinkisharyo">{{cite web |date=December 18, 2014 |title=Sound Transit Motion No. M2014-105 |url=https://www.soundtransit.org/sites/default/files/documents/pdf/about/board/motions/2014/Motion_M2014-105.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170918110547/https://www.soundtransit.org/sites/default/files/documents/pdf/about/board/motions/2014/Motion_M2014-105.pdf |archive-date=September 18, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref><ref>{{cite press release |date=December 17, 2006 |title=Sound Transit unveils first Central Link light rail vehicle |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Central-Link-Vehicle |publisher=Sound Transit |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170918112216/https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/Central-Link-Vehicle |archive-date=September 18, 2017}}</ref> Another 27 vehicles were ordered for the University Link extension in 2009 and were delivered from 2010 to 2011.<ref name="ST-2014Kinkisharyo"/> The 1{{nbsp}}Line fleet is stored and maintained at a {{convert|26|acre|1|adj=mid}} operating base in SoDo, between SODO and Beacon Hill stations. It opened in 2007, at a cost of $74&nbsp;million to construct, and has a capacity of 105 light rail vehicles, including nine bays inside the {{convert|162,000|sqft|sqm|adj=mid}} maintenance building that can hold 16 vehicles.<ref>{{cite report |url=https://www.soundtransit.org/sites/default/files/documents/pdf/projects/OMSF/OMSF_Task_2.3B_Core_Light_Rail_System_Plan_Review.pdf |title=Link Operations & Maintenance Satellite Facility: Core Light Rail System Plan Review |date=September 2012 |publisher=Sound Transit |page=1 |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20150910083741/http://www.soundtransit.org/sites/default/files/documents/pdf/projects/OMSF/OMSF_Task_2.3B_Core_Light_Rail_System_Plan_Review.pdf |archive-date=September 10, 2015 |url-status=live}}</ref><ref>{{cite press release |date=March 4, 2007 |title=ST opens state-of-the-art Link light rail Operations & Maintenance Facility |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/OM-Dedication |publisher=Sound Transit |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170918110641/https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/News-release-archive/OM-Dedication |archive-date=September 18, 2017}}</ref><ref>{{cite news |last=Cohen |first=Aubrey |date=June 16, 2009 |title=Here's where they fix the light rail trains |work=Seattle Post-Intelligencer |url=https://www.seattlepi.com/local/article/Here-s-where-they-fix-the-light-rail-trains-1304591.php |access-date=February 28, 2020}}</ref> 1{{nbsp}}Line trains are operated and maintained by [[King County Metro]] under a contract with Sound Transit that was renewed in 2019 and is set to expire at the end of 2023.<ref>{{cite web |date=September 2016 |title=2017 Proposed Budget |url=https://www.soundtransit.org/sites/default/files/20161005-proposed-2017-budget.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170918112250/https://www.soundtransit.org/sites/default/files/20161005-proposed-2017-budget.pdf |archive-date=September 18, 2017 |access-date=September 17, 2017 |publisher=Sound Transit |page=32}}</ref><ref>{{cite press release |date=April 29, 2019 |title=King County Metro, Sound Transit reach agreement to continue integrated rail operations and maintenance through 2023 |url=https://kingcounty.gov/elected/executive/constantine/news/release/2019/April/29-metro-rail.aspx |publisher=King County Executive's Office |accessdate=April 25, 2022}}</ref>

In September 2016, Sound Transit approved a $554&nbsp;million order to [[Siemens Mobility]] for 122 [[Siemens S700 and S70|S700]]{{efn|name=retroactive-rebrand|At the time of purchase and receipt of the first cars, the second generation of light rail vehicles were a version of Siemens' model S70, but Siemens retroactively rebranded this version as the S700 in 2020.<ref name="taut-2020sep">{{cite news |author=<!--Staff writer(s); no by-line.--> |title=Siemens rebadges North American low-floor cars |date=September 2020 |magazine=[[Tramways & Urban Transit]] |page=336 |publisher=Mainspring Enterprises Ltd. |location=UK |number=993 |issn=1460-8324}}</ref>}} "Series&nbsp;2" light rail vehicles to serve planned extensions to Northgate, Lynnwood, the Eastside, and Federal Way.<ref>{{cite news |last=Demay |first=Daniel |date=September 22, 2016 |title=Sound Transit places $554M order for more light rail cars |work=[[Seattle Post-Intelligencer]] |url=http://www.seattlepi.com/local/transportation/article/Sound-Transit-places-554M-order-for-more-light-9240587.php |url-status=live |access-date=September 29, 2016 |archive-url=https://web.archive.org/web/20160930145238/http://www.seattlepi.com/local/transportation/article/Sound-Transit-places-554M-order-for-more-light-9240587.php |archive-date=September 30, 2016}}</ref> Another 30 vehicles were added to the order in April 2017, bringing the total to 152 vehicles.<ref>{{cite press release |date=April 27, 2017 |title=Sound Transit to order 30 additional light rail vehicles |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/sound-transit-order-30-additional-light-rail |publisher=Sound Transit |access-date=July 16, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170716111901/https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/sound-transit-order-30-additional-light-rail |archive-date=July 16, 2017}}</ref> The first Series&nbsp;2 car arrived at Sound Transit's maintenance facility in June 2019, featuring the same seating capacity but a wider central walkway and other new features.<ref>{{cite news |last=Lindblom |first=Mike |date=June 19, 2019 |title=Sound Transit shows off its new, roomier light-rail cars. They'll go into service next year |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/sound-transit-shows-off-its-new-roomier-light-rail-cars-theyll-go-into-service-next-year/ |url-access=limited |access-date=June 19, 2019}}</ref><ref>{{cite press release |date=December 18, 2020 |title=Testing of Link's new light rail vehicles during service hours starts Dec. 19 |url=https://www.soundtransit.org/get-to-know-us/news-events/news-releases/testing-links-new-light-rail-vehicles-during-service-hours |publisher=Sound Transit |access-date=February 2, 2021}}</ref> The first Siemens cars entered service on May 14, 2021.<ref name="RA-Siemens">{{cite news |last=Luczak |first=Marybeth |date=May 17, 2021 |title=New Sound Transit LRVs Enter Service |work=[[Railway Age]] |url=https://www.railwayage.com/passenger/light-rail/new-sound-transit-lrvs-enter-service/ |access-date=May 19, 2021}}</ref> A satellite maintenance facility in Bellevue was opened in 2021 to accommodate 96 more vehicles, including part of the new fleet and older Series&nbsp;1 vehicles undergoing retrofit work.<ref>{{cite press release |date=May 20, 2021 |title=Sound Transit completes new light rail base in Bellevue |url=https://www.soundtransit.org/get-to-know-us/news-events/news-releases/sound-transit-completes-new-light-rail-base-bellevue |publisher=Sound Transit |accessdate=May 23, 2023}}</ref><ref>{{cite news |last=Wanek-Libman |first=Mischa |date=May 17, 2021 |title=Sound Transit puts first Series 2 light-rail vehicles into service |url=https://www.masstransitmag.com/rail/vehicles/article/21222932/sound-transit-puts-first-series-2-lightrail-vehicles-into-service |work=[[Mass Transit Magazine]] |accessdate=May 23, 2023}}</ref> A third facility is planned to be built near Federal Way to support future system expansion.<ref>{{cite news |last1=Lindblom |first1=Mike |last2=Baruchman |first2=Michelle |date=August 15, 2021 |title=Sound Transit faces a $6.5 billion shortfall. Here's what it might do |url=https://www.seattletimes.com/seattle-news/transportation/sound-transit-faces-a-6-5-billion-shortfall-heres-what-it-might-do/ |work=The Seattle Times |accessdate=May 23, 2023}}</ref>

==Future plans==
{{main|Link light rail#Future expansion}}

Sound Transit's expansion ballot measures, passed as [[Sound Transit 2]] in 2008 and [[Sound Transit 3]] in 2016, enabled the planning of future Link light rail extensions, scheduled to open in stages between 2021 and 2040.<ref name="2018SIP">{{cite web |date=October 2017 |title=Draft 2018 Service Implementation Plan |url=https://www.soundtransit.org/sites/default/files/2018-service-implementation-plan.pdf |url-status=live |archive-url=https://web.archive.org/web/20180119063248/https://www.soundtransit.org/sites/default/files/2018-service-implementation-plan.pdf |archive-date=January 19, 2018 |access-date=October 28, 2017 |publisher=Sound Transit |pages=54–55}}</ref><ref name="ST3-Map">{{cite map |date=March 2022 |title=Sound Transit Future Service |url=https://www.soundtransit.org/sites/default/files/documents/st-future-service-map.pdf |publisher=Sound Transit |access-date=May 23, 2023}}</ref> The [[Northgate Link extension]] opened on October 2, 2021, and extended the 1&nbsp;Line by three stations to the north end of Seattle.<ref name="RA-Northgate"/> It was followed by the [[2 Line (Sound Transit)|2 Line]] in 2024, a new line to Bellevue and [[Redmond, Washington|Redmond]], that will be extended west to Seattle in 2025.<ref>{{cite news |last=Lindblom |first=Mike |date=August 24, 2023 |title=Eastside-only light rail should open in March, Sound Transit says |url=https://www.seattletimes.com/seattle-news/transportation/eastside-only-light-rail-should-open-march-2024-sound-transit-says/ |work=The Seattle Times |accessdate=August 30, 2023}}</ref> During construction related to the 2 Line (then called East Link) in early 2020, trains within the downtown transit tunnel were temporarily limited to single-track operations and divided into two lines at Pioneer Square station.<ref>{{cite news |last=Lindblom |first=Mike |date=February 7, 2019 |title=Sound Transit prepares for its own construction squeeze in 2020 |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/sound-transit-prepares-for-its-own-construction-squeeze-in-2020/ |url-access=limited |access-date=February 7, 2019}}</ref>

As part of the Sound Transit 2 program, the 1{{nbsp}}Line will be extended south to [[Federal Way, Washington|Federal Way]] by 2026.<ref>{{cite news |last=Lindblom |first=Mike |date=August 18, 2022 |title=More delays for light rail to Bellevue, Redmond, Federal Way, Lynnwood |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/more-delays-for-light-rail-to-bellevue-redmond-federal-way-lynnwood/ |accessdate=August 18, 2022}}</ref><ref>{{cite news |last=Sailor |first=Craig |date=December 30, 2022 |title=Sound Transit's Federal Way Link extension 63% complete but Tacoma connection slows |url=https://www.thenewstribune.com/news/local/article270286667.html |work=The News Tribune |accessdate=May 23, 2023}}</ref>

In 2032, the [[3 Line (Sound Transit)|3&nbsp;Line]] to [[West Seattle, Seattle|West Seattle]] will begin service, temporarily operating between Alaska Junction and SODO station.<ref>{{cite web |date=September 2017 |title=West Seattle and Ballard Link Extensions: Project Overview |url=https://www.soundtransit.org/sites/default/files/project-documents/west-seattle-ballard-project-overview.pdf |url-status=dead |archive-url=https://web.archive.org/web/20170917051725/https://www.soundtransit.org/sites/default/files/project-documents/west-seattle-ballard-project-overview.pdf |archive-date=September 17, 2017 |access-date=September 17, 2017 |publisher=Sound Transit}}</ref> The opening of an extension to Ballard by 2039, traveling via a new tunnel through Downtown Seattle,<ref name="ST3-2017">{{cite press release |date=April 27, 2017 |title=Sound Transit takes its game to the next level with kickoff of massive infrastructure investments |url=https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/sound-transit-takes-its-game-next-level-kickoff |publisher=Sound Transit |access-date=September 17, 2017 |url-status=live |archive-url=https://web.archive.org/web/20170918110608/https://www.soundtransit.org/About-Sound-Transit/News-and-events/News-releases/sound-transit-takes-its-game-next-level-kickoff |archive-date=September 18, 2017}}</ref><ref>{{cite news |last=Lindblom |first=Mike |date=August 5, 2021 |title=Two light-rail stations in Seattle escape ST3 budget chopping, most other projects delayed |work=The Seattle Times |url=https://www.seattletimes.com/seattle-news/transportation/two-light-rail-stations-in-seattle-escape-st3-budget-chopping-most-other-projects-delayed/ |access-date=August 13, 2021}}</ref> will split the corridor between two lines: the 1{{nbsp}}Line, operating from Ballard to Tacoma via the Rainier Valley and Sea-Tac Airport; and the 3{{nbsp}}Line, operating from Lynnwood (and later [[Everett, Washington|Everett]]) to West Seattle.<ref name="ST3-Map"/><ref>{{cite web |date=April 7, 2016 |title=LRT System Operations and OMF Assumptions |url=http://www.wsdot.wa.gov/partners/erp/background/ST3%20Operations%20and%20Administration%20presentation.pdf |url-status=live |archive-url=https://web.archive.org/web/20170211145808/http://www.wsdot.wa.gov/partners/erp/background/ST3%20Operations%20and%20Administration%20presentation.pdf |archive-date=February 11, 2017 |access-date=September 17, 2017 |publisher=Sound Transit |via=Washington State Department of Transportation}}</ref> Two [[infill station]]s along the current route of the 1{{nbsp}}Line are planned to open in 2031 at South Graham Street in the Rainier Valley and Boeing Access Road in northern Tukwila.<ref>{{cite news |last=Lindblom |first=Mike |date=November 14, 2016 |title=Where Sound Transit 3 projects could speed up or slow down |page=B1 |work=The Seattle Times |url=http://www.seattletimes.com/seattle-news/transportation/where-sound-transit-3-projects-could-speed-up-or-slow-down/ |url-status=live |url-access=limited |access-date=September 17, 2017 |archive-url=https://web.archive.org/web/20170828005549/http://www.seattletimes.com/seattle-news/transportation/where-sound-transit-3-projects-could-speed-up-or-slow-down/ |archive-date=August 28, 2017}}</ref>

==Notes==
{{notelist}}

==References==
{{reflist}}

==External links==
{{Attached KML|display=title,inline}}

* {{commons category-inline}}
* [http://www.soundtransit.org/ Official Sound Transit website]

{{Puget Sound Transit}}
{{USLightRail}}

{{authority control}}

[[Category:1500 V DC railway electrification]]
[[Category:2009 establishments in Washington (state)]]
[[Category:Airport rail links in the United States|Seattle]]
[[Category:Link light rail]]
[[Category:Railway lines opened in 2009]]
[[Category:Transportation in King County, Washington]]
[[Category:Transportation in Seattle]]
[[Category:Naming controversies]]