From the Black Hills to the Ozarks and the Wisconsin Dells to the Texas Hill Country, Cavern.com identifies 32 showcaves. They include the longest underground navigable river, the ultra-rare black alabaster, species of sightless cave-dwelling creatures and breathtaking formations of size and beauty. Here are some highlights:
- Rushmore Cave near Keystone, S.D., is in a limestone formation encircling the granite core of the Black Hills. Its four rooms are the Post Office, where early visitors carved their initials; the Image Room, with face-shaped formations; the Floral Room, with helictites on stalactites in leaf and floral design; and the Big Room, with numerous stalactites, flowstone, and cave bacon.
- Cave of the Mounds near Blue Mounds, Wis., discovered in 1939, is considered the most significant cave in the upper Midwest by the Chicago Academy of Sciences. It has a high number of colorful crystal formations on paved lighted pathways.
- Bluespring Caverns in Lawrence County, Ind., contains 21 miles of surveyed passages and the longest U.S. subterranean river with 3 navigable miles. It is home to crayfish, salamanders, crickets, spiders, beetles, bats and the rare sightless Northern Cavefish.
Marengo Cave in Crawford County, Ind., discovered in 1883 and open to the public from the beginning, has almost five miles of known passageway.- Spook Cave near McGregor, Iowa, opened in 1955, is explored entirely by boat on the underground water.
- Crystal Lake Cave near Dubuque, Iowa, was discovered in 1868 and contains crystals including aragonite, travertine, satin stalagmite, stalactite and calcareous spar.
- Alabaster Caverns near Freedom, Okla., has the largest natural gypsum cave in the world, including, pink, white and rare black alabaster, otherwise found only in China and Italy.
- Mark Twain Cave near Hannibal, Mo., was discovered by hunters about 1820 and contains tools of earlier Native Americans who used the cave. Mark Twain visited the cave and based a scene in The Adventures of Tom Sawyer on his experience.
- Meramec Caverns near Stanton, Mo., is the largest commercial cave in the state that has more than 6,000 surveyed caves. The system is 4.6 miles long.
- Bluff Dwellers Cave near Noel, Mo., was used by the ancient peoples known as Bluff Dwellers. It was open to the public in 1927.
- Talking Rocks Cavern in Stone County, Missouri, was named Fairy Cave by its early developer for its glittering crystals. (Glenwood Caverns Adventure Park in Glenwood Springs also has a cave with the same name and offers tours of the Historic Fairy Caves)
- War Eagle Cavern on Beaver Lake near Rogers, Ark., contains unusual domes, rimstone dams, and underground streams and waterfalls. It was used by moonshiners before the lake was built in the 1960s.
Mystic Cavern and Crystal Dome Cavern are less than 400 feet apart near Harrison, Ark. Mystic has a Pipe Organ calcite formation 30 feet tall and 12 feet thick as well as helictites, shields and spherical stalactites. Crystal has a 70-foot dome and other dripstone formations of pure while calcite.- Cave Without A Name near Boerne, Tex., has six rooms with formations of stalactites, stalagmites, soda straws, cave drapery, flowstones and rimstone dams. Concerts are held in the Cave Throne Room.
- Caverns of Sorona near Sorona, Tex., is in a limestone formation at the frontier of the Hill Country and the Chihuahuan Dessert. It was discovered in the early 1920s and opened to the public in 1960.
- Inner Space Cavern near Georgetown, Tex., was discovered in 1963 and opened to the public in 1966. Mammoth and saber-tooth cat bones have been discovered in the ancient cave.
- Natural Bridge Cavern near San Antonio, Tex., has a 60-foot limestone bridge. It was discovered in 1960 and opened in 1964.
- Longhorn Cavern in Burnet County, Tex., was used by Native Americans, Confederate soldiers, outlaws, and, during Prohibition, as a speakeasy with musical performances. It was explored, cleaned and improved by the Civilian Conservation Corps during the Great Depression. Musicians started performing in the cavern again in 2006.
