Rushmore Cave into a rock known as limestone. The cave has a cornucopia of rooms including the Entrance Room, Post Office, Image Room, Big Room, Fairyland, Rope Room, Geode Room, The Rouge Room (Party Room), Arrowhead Room, and the Floral Room. The cave also includes boxwork and many dripstone formations including stalactites, stalagmites, columns, helictites and flowstone. Rushmore Cave Rushmore Cave is the closest show cave to Mount Rushmore National Memorial in the United States. It contains a wide variety of natural formations. It is the ninth longest cave in South Dakota. It measures a distance of . It was discovered in
Mount Rushmore in popular culture the final battle with the Forever King. Another group shown as having a secret base inside the mountain is the "All Purpose Enforcement Squad" of "Young Justice", in the DC Universe series. The comic book superhero Mister Majestic, a character in the Wildstorm Productions universe, also had a secret base of operations inside Mount Rushmore, analogous to Superman's "Fortress of Solitude". In "", a 1981 animated movie jointly produced by Hanna-Barbera and Tsuburaya Productions, the heroic Ultra Force is headquartered within Mount Rushmore. Mount Rushmore was a primary location of interest in the plot of the 2007 film "" starring