Twin Peaks Tunnel

Twin Peak Tunnel is a rail tunnel used by the Muni Metro system under the Twin Peaks connecting Castro District and southwestern side of San Francisco. It is used by the K Ingleside (outbound to City College), L Taraval, M Ocean View, and T Third Street (inbound to Downtown) lines. At the north/east end, tracks continue underground to Downtown San Francisco as part of the Market Street Subway. At the south/west end, the street cars exit the tunnel onto surface streets.

Twin Peak Tunnel was constructed in 1918 and connects to surface tracks in the Castro before the opening of the Market Street Subway for Muni Metro in 1980.

Line and stations

					Market Street Subway to Downtown SF
Castro Station					The Castro
Forest Hill Station
West Portal Station
					to surface streets

Alternatives

During major service interruption of the tunnel, while Muni may provide bus shuttle service, riders should also consider surface transit options (buses) as alternative, either direct to downtown or connect with BART in Balboa Park or other stations.