What's the attraction: Moaning Cavern has the largest vertical chamber in any of the California cavern systems open to the public. The 45-minute walking tour takes visitors down 234 steps deep under the ground, where you can see fascinating rock formations and learn about thousands of years of California history and an even longer span of geology. But, as intriguing as the walking tour is, that’s not the best part.
For the adventurer: For visitors over 12, skip the stairs and try rappelling into the cavern. The options are a 45-minute tour that covers the same ground as the walking tour, or the three-hour Adventure Trip, which starts with (optional) rappelling into the main cavern, then climbing and crawling through undeveloped tunnels not normally open to the public.