Downtown Rail Extension Overview

The Downtown Rail Extension (DTX) will extend Caltrain 1.3 miles underground from its current terminus at 4th and King streets into the new downtown Transit Center and accommodate California’s future High Speed Rail from San Francisco to Los Angeles/Anaheim.


The Metropolitan Transportation Commission (MTC) and the Association of Bay Area Governments (ABAG) jointly approved a Regional Transportation Plan (RTP) that designates the DTX as a regional priority for the federal New Starts program. New Starts is the federal government’s primary financial resource for supporting this type of transit capital investment. As a regional priority for New Starts, the project will begin working with the U.S. Department of Transportation (DOT) towards a Full Funding Grant Agreement that would allow for construction of the DTX.



Caltrain already serves as a vital regional link by connecting San Francisco to the Peninsula, Silicon Valley and San Jose, but it currently ends 1.3 miles from downtown San Francisco. The DTX will extend the Caltrain rail line into the new Transit Center, the heart of San Francisco’s new downtown. Extending Caltrain into downtown will directly save commuters almost an hour a day in travel time, and will result in less driving and more people taking the train into the City from the Peninsula. More than 33,000 Peninsula passengers will use the Transit Center each weekday. The underground rail line will run from Caltrain’s current terminus at 4th and King street beneath Second Street and into the new Transit Center