Caving & Cave Exploration

California's underground is as varied as its surface, and four completely different geologies built it. Lava tubes: Lava Beds National Monument alone holds more than 800 of them, with Subway Cave and Pluto's Cave adding roadside volcanic tubes nearby. Limestone: Crystal Cave in Sequoia, Boyden Cavern in Kings Canyon, and the Gold Country show caves — Moaning, Mercer, Black Chasm and California Cavern — grew drop by drop across millions of years. Talus caves formed where boulders wedged into narrow canyons, most famously at Pinnacles National Park. And sea caves carved straight out of the Pacific include Painted Cave on Santa Cruz Island, among the largest on earth, the La Jolla sea caves, and the arches at El Matador. Add Chumash rock art at Painted Cave and the Batcave in Bronson Canyon, and filter by tier, self-guided access, and first-timer suitability.