Fort Mason Tunnel
former rail tunnel in San Francisco

Fort Mason Tunnel is an abandoned single-track railway tunnel in San Francisco which runs under a small hill upon which sits a portion of the old Fort Mason. The tunnel was constructed in 1913 and opened to rail traffic in 1914. The east portal is near the north end of Van Ness Avenue; the west portal feeds onto Marina Boulevard at Laguna Street.
History
The tunnel's construction served several purposes. The rail link supplied goods and mass transit to the Panama Pacific International Exposition the following year; the U.S. Army utilized the line for construction of the port of embarkation at Fort Mason. The tunnel operated as part of the State Belt Railroad until the route's suspension in 1993. A portion of the movie Dirty Harry was filmed on either side of the tunnel in 1971.
Future
In 2012, the National Park Service released a final environmental impact report on providing extended service through the tunnel to the San Francisco Municipal Railway F Market & Wharves line. The cost of refurbishment and extension of the rail line was estimated at $60 million in 2017.
This brief starts where responsible research should: with the source description of “Fort Mason Tunnel” as former rail tunnel in San Francisco. Everything that follows is an evidence route, not borrowed authority.
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Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Jul 23, 2026. The linked authority identifier is Q20861638. Authority coordinates are 37.805, -122.431. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1913, 1914, 1993 and 1971.
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This entry incorporates text from “Fort Mason Tunnel” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.