The Mark Twain Cave and Cameron Cave exhibits in Hannibal are two of the oldest show caves in Missouri. The Mark Twain Cave actually is the oldest show cave, having first gone on display in 1820. Many years later, when Mark Twain was still Sam Clemens, he would make the cave a favorite play and stomping ground.
Twain would make the cave quite famous in his book The Adventures of Tom Sawyer, the 55 minute tour of the cave mentions all the scenes from the book that are used in the cave. Also, the descriptive narrative in the book has been remarked to quite accurately reflect the cave in several visitor reviews. Less attentive readers of Twain's work should note that this includes seeing bats in the cave during the tour.
Cameron Cave came on the scene nearly 100 years later, becoming a show cave in 1925. The two caves are quite close to each other, and share a common campground. Cameron Cave is a bit more involved, and the average tour runs for more than 90 minutes. It is cool in the caves and suggested that visitors wear coats and be prepared for the chill.
Both caves receive high marks from visitors for not being "overly commercial''. The cave tours are rustic, with lantern lighting carried by participants. There are bats and rough grounds. However, both caves are also noted for their extreme beauty - one visitor described it as being able to see a slice of Earth from the inside.
Cameron Cave is not open in winter, although the Mark Twain cave is open year-round. Neither cave is open on major holidays, and the peak visiting season is between Memorial Day and Labor Day. During the high season, tours run three times daily although times vary somewhat. Admission discounts are given for viewers of both caves; tickets run between $15 - $20 per person.
