10 Hidden Underground Spaces in San Francisco You Didn’t Know Existed

1. The Speakeasy at Bourbon & Branch

📍 501 Jones St, San Francisco, CA 94102
A hidden door, a secret password, and no cell phones allowed—Bourbon & Branch takes you back to the 1920s, with a maze of underground rooms used during Prohibition.

2. The Abandoned Tunnels of Fort Miley

📍 Fort Miley Military Reservation, Point Lobos Ave & 48th Ave, San Francisco, CA 94121
Buried beneath the trees at Lands End, the Fort Miley tunnels were part of a WWII coastal defense system. Some of them are still accessible if you know where to look.

3. The Secret Basement at City Lights Bookstore

📍 261 Columbus Ave, San Francisco, CA 94133
San Francisco’s legendary bookstore has a basement room filled with rare books and Beat Generation artifacts, open only to those who ask.

4. The Abandoned BART Station Below Market Street

📍 Near Embarcadero Station, Market St, San Francisco, CA 94105
Deep beneath Market Street lies a never-used BART station built in the ’60s. It’s still there, untouched, hidden beneath the current train tunnels.

5. The Hidden Tunnels Under Chinatown

📍 Chinatown District, San Francisco, CA 94108
Rumors swirl about century-old tunnels under Chinatown, used for smuggling, secret passageways, and underground gambling dens. While most entrances are sealed, some shop basements still lead to them.

6. The Wine Caves Under the Fairmont Hotel

📍 950 Mason St, San Francisco, CA 94108
During Prohibition, the Fairmont Hotel’s basement housed hidden wine cellars and secret passageways for bootlegging. Some are still intact.

7. The Forgotten Bank Vault at the Mechanics’ Institute

📍 57 Post St, San Francisco, CA 94104
This 19th-century library was once a private club for SF’s elite. A massive underground vault remains beneath the building, though it’s rarely open to the public.

8. The Hidden Rooms Under the Palace of Fine Arts

📍 3301 Lyon St, San Francisco, CA 94123
Beneath the Palace of Fine Arts is a network of storage rooms and passageways that were part of the 1915 Panama-Pacific Expo. Some remain accessible today.

9. The Secret Catacombs of St. Mary’s Cathedral

📍 1111 Gough St, San Francisco, CA 94109
San Francisco’s oldest cathedral has underground crypts and a hidden network of tunnels, used in the past for burials and priest passageways.

10. The Cold War Bunker Beneath Twin Peaks

📍 Twin Peaks Summit, San Francisco, CA 94114
Underneath Twin Peaks lies a decommissioned military bunker, once part of SF’s missile defense system. Though sealed off, you can still find traces of it at the summit.

Most people don’t realize just how much of San Francisco exists beneath the city. Whether you’re an urban explorer or just curious about history, these underground spaces offer a glimpse into SF’s hidden past.

Please note that some of these locations are on private property or may be unsafe to explore without proper authorization and precautions.