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 birds, including songbirds, nuthatches, and woodpeckers, inhabit the surrounding pine forests. Terrestrial mammals include the mouse, least chipmunk, red squirrel, skunk, porcupine, raccoon, beaver, badger, coyote, bighorn sheep, bobcat, elk, mule deer, yellow-bellied marmot, and American bison. The striped chorus frog, western chorus frog, and northern leopard frog also inhabit the area, along with several species of snake. Grizzly Bear Brook and Starling Basin Brook, the two streams in the memorial, support fish such as the longnose dace and the brook trout. Mountain goats are not indigenous to the region. Those living near Mount Rushmore are descendants of a tribe