The hook
A working scale model of the entire San Francisco Bay, the size of two football fields, with tides that cycle every fourteen minutes.
01Why it's worth it
In a plain warehouse on the Sausalito waterfront, the Army Corps of Engineers built a hydraulic model of the whole bay and delta in the 1950s, to test what would happen if someone dammed and filled the South Bay (someone had seriously proposed it). It fills a space the size of two football fields, real water flows through it, and pumps recreate the tides on a compressed clock, a full tidal day every fourteen minutes, so you can literally watch the bay breathe. Computers made it scientifically obsolete, but they kept it as a public exhibit, and walking the catwalks over a living, sloshing miniature of the entire bay, reading the little concrete shorelines, is mesmerizing and completely free.
02How to experience it
It's in the Bay Model Visitor Center on Sausalito's waterfront, the old WWII Marinship yard. Free, but closed some weekdays, so check the hours, and try to be there when they're running the tides. Easy to reach by ferry or bike from the city.
From the locals
It's a recurring answer to "most fascinating places in the Bay": "the Bay Model just off the GG Bridge in Sausalito, not necessarily weird, but very fascinating," and "it's huge and worthy of a visit."