Jewel Cave National Monument
11149 U.S. Highway 16, Building B12
Custer, South Dakota 57730
605-673-2288 or 605-673-8300
Filled with calcite spar crystals, gypsum, frostwork, boxwork, hydromagnesite balloons, stalactites, boulders, tight crawlways and dark fissures, Jewel Cave is the second longest cave in the world at more than 150 feet. The main Visitor Center and cave entrance is 13 miles west of Custer, South Dakota on Route 16, 24 miles east of Newcastle, Wyoming.