Link light rail is a light rail rapid transit system serving the Seattle metropolitan area in the U.S. state of Washington. It is managed by Sound Transit in partnership with local transit providers, and consists of two non-connected lines: the 1 Line (formerly Central Link) in King County, which travels for between Seattle and Seattle–Tacoma International Airport; and the T Line (formerly Tacoma Link) in Pierce County, which runs for between Downtown Tacoma and Tacoma Dome Station. In , the system had a ridership of 23.9 million, or about per weekday as of , primarily on the 1 Line. Trains run at frequencies of 6 to 24 minutes.
The Link light rail system was originally conceived in the 1980s following several earlier proposals for a heavy rail system that were rejected by voters. Sound Transit was created in 1993 and placed a ballot measure to fund and build the system, which was passed on a second attempt in 1996. Tacoma Link began construction first in 2000 and opened on August 22, 2003, at a cost of $80 million. Central Link construction was delayed because of funding issues and routing disputes, but began in November 2003 and was completed on July 18, 2009, for $2.4 billion. Central Link trains initially ran from Downtown Seattle to Tukwila International Boulevard station before being extended south to the airport in December 2009, north to the University of Washington in March 2016, and further south to Angle Lake station in September 2016. An extension to Northgate station opened on October 2, 2021.
Sound Transit plans to expand the Link light rail network to and 70 stations by 2044, using funding approved by voters in 2008 and 2016 ballot measures. An extension from the University of Washington to Northgate opened on October 2, 2021. Suburban extensions to Bellevue, Redmond, Lynnwood, and Federal Way are scheduled to open between 2024 and 2026 after construction delays. Later projects will expand the system to cover the metropolitan area from Everett to Tacoma, along with branches to Kirkland, Issaquah, and the Seattle neighborhoods of Ballard and West Seattle.
History
The first public transit networks in the Puget Sound region were various streetcar, cable cars, and interurbans constructed in the late 19th and early 20th centuries, which spurred the development of streetcar suburbs. Some of these systems were consolidated into the Seattle Municipal Street Railway, a city-owned network established in 1918, while others remained under the operation of their private owners. Unsuccessful proposals for a rapid transit system to connect Seattle's neighborhoods, and later other cities in the region, also emerged during the peak and later decline of streetcar and interurban service, both of which were dismantled by 1941.
Following the 1968 and 1970 rejection of the Forward Thrust ballot measure to build a rapid transit system, voters in King County approved the creation of a new countywide bus system under the management of Municipality of Metropolitan Seattle, an existing water treatment and sewage agency. The system began operating in 1973 and later included the construction of the Downtown Seattle Transit Tunnel in the late 1980s to relieve bus congestion on downtown streets. Metro and the Puget Sound Council of Governments also began planning a regional transit system at that time; a joint 1981 study named light rail as the preferred mode that would be able to operate on streets in some areas but generally follow freeway corridors to regional centers. A non-binding advisory ballot measure on further development of a light rail system approved by voters in 1988. Metro's transit tunnel opened for buses in September 1990 and included tracks and electrical systems that would be compatible for future conversion to light rail.