Jewel Cave National Monument

Address: 
11149 U.S. Highway 16, Building B12, Custer

Immerse yourself within the third longest cave in the world. With over 177 miles of mapped and surveyed passages, this underground wilderness appeals to human curiosity. Its splendor is revealed through fragile formations and glimpses of brilliant color. Its maze of passages lure explorers, and its scientific wealth remains a mystery. This resource is truly a jewel in the National Park Service.