Downtown Seattle Transit Tunnel

The Downtown Seattle Transit Tunnel (DSTT), formerly also known as the Metro Bus Tunnel, is a 1.3-mile-long (2.1 km) pair of public transit tunnels in Seattle, Washington, United States. The double-track tunnel and its four stations serve Link light rail trains on the 1 Line as it travels through Downtown Seattle. It runs west under Pine Street from 9th Avenue to 3rd Avenue, and south under 3rd Avenue to South Jackson Street. 1 Line trains continue north from the tunnel to Lynnwood City Center and south through the Rainier Valley past Seattle–Tacoma International Airport to Federal Way Downtown station as part of Sound Transit's light rail network. The DSTT was used only by buses from its opening in 1990 until 2005, and shared by buses and light rail from 2009 until 2019. Bus routes from King County Metro and Sound Transit Express left the tunnel north via Interstate 5, south via the SODO Busway, or east via Interstate 90. It was owned by King County Metro and shared with Sound Transit through a joint-operating agreement signed in 2002; Sound Transit assumed full ownership in 2022. The Downtown Seattle Transit Tunnel was one of two tunnels in the United States shared by buses and trains, the other being the Mount Washington Transit Tunnel in Pittsburgh, and was the only one in the United States with shared stations. Though proposals for a rapid transit tunnel under 3rd Avenue w

Tunnel data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).