San Andreas – It’s not our fault.

Earthquake Thriller Shines Light on Gold Rush Town

San Andreas, California
Historic Main Street San Andreas | Wikipedia

The 2015 opening of a Hollywood film titled “San Andreas” called attention to the Gold Rush town of the same name. The film depicts a fictional version of the San Andreas fault, which runs through western California and is unrelated to the town of San Andreas in Calaveras County, situated in the east. Ironically enough, San Andreas the town, is so seismically insignificant that a recent search of the U.S. Geological Survey’s website at showed that it barely rated any kind of mention.

So where does this confusing nomenclature come from? Simply this: the town was named after San Andrés, the patron saint of Spain. Mexicans first discovered gold here, and by the early 1850s between 1,000 and 1,500 miners were working in the area. In 1854 extensive placer deposits were discovered in an old riverbed 150 feet below the surface of the earth.

As the County seat, San Andreas is the center of commerce, education and services for Calaveras County. The town also boasts a small, delightful historic district that captures the charm of earlier eras and houses the Calaveras County Archives and Calaveras County Museum Complex.

California Cavern caving expedition
California Cavern caving expedition | Photo: Dave Bunnell

With no noticeable subterranean shaking, you can still get your thrills underground at nearby California Cavern, State Historic Landmark, in Mountain Ranch. As the state’s first show cave, opened in 1849 or 1850 (stories vary), early Gold Rush hopefuls used the cave for entertainment – in some strange ways that we wouldn’t ever consider today. Current walk tours explore passages and chambers detailing this interesting social history of the cave’s many uses including as a place for secret political meetings, a hideout for Black Bart, a wedding ceremony venue, and one of the most unusual liquor bar locations.

Explore more San Andreas’ highlights here.

Fast forward to the 21st century, and extended wild cave expeditions (by reservation) are also offered, taking visitors far beyond the walking tour areas of the cave, to climb, crawl and slither through deep recesses of mud, underground lakes, ravines decorated overhead with sparkling, crystalline formations on 2 and 4-hour adventure spelunking trips. The Mammoth Cave Expedition, available for ages 8 and up is a perfect family activity and great introduction to the sport of caving or spelunking. The Middle Earth Expedition, a full-on immersive tour for those with an adventurous bent is available for ages 16 and up. And if you want an obvious sign that earthquakes aren’t a big deal in Calaveras. Just look up at the ceiling in California Cavern or any of Calaveras’ cave systems. Those fragile calcite formations have decorated the caves for eons. Any significant shaking, and they’d be gone. Case closed.

California Cavern Jungle Room
California Cavern Walk Tour | Photo: Dave Bunnell

You can make reservations for California Cavern’s caving expeditions by calling 866-762-2837 or 209-736-2708 or by emailing No reservations are necessary for walk tours.

Get full details on things to see and do in Calaveras from our digital Acitivities Guide.