During his first term as mayor, Brown quietly favored the demolition and abolition of the Transbay Terminal to accommodate the redevelopment of the site for market-rate housing. Centrally located at First and Mission Streets near the Financial District and South Beach, the terminal originally served as the San Francisco terminus for the electric commuter trains of the East Bay Electric Lines, the Key System of streetcars and the Sacramento Northern railroads which ran on the lower deck of the San Francisco–Oakland Bay Bridge. Since the termination of streetcar service in 1958, the terminal has seen continuous service as a major bus facility for East Bay commuters; AC Transit buses transport riders from the terminal directly into neighborhoods throughout the inner East Bay. The terminal also serves passengers traveling to San Mateo County and the North Bay aboard SamTrans and Golden Gate Transit buses respectively, and to tourists arriving by bus motorcoach. Today, the terminal is being planned for redevelopment as a regionwide mass transit hub maintaining the current bus services, but with a new tunnel that would extend the Caltrain commuter rail line from its current terminus at Fourth and Townsend Streets to the site. Once completed, Caltrain riders would no longer need to transfer to Muni to reach the downtown financial district, and the terminal's heavy rail portion would be designed to accommodate the planned High Speed Rail lines to Los Angeles.