Jewel Cave National Monument

Jewel Cave National Monument is a protected cave system and surface park in western South Dakota, established as a national monument in 1908. It is notable for its extensive mapped passages and abundant calcite formations that give the cave its name.

The underground network includes more than 200 miles of mapped passages with varied calcite decorations and narrow to roomy passages; ranger-guided tours range from short, accessible routes to longer, more strenuous options. Above ground there is a visitor center, short trails, and a scenic loop drive that provide viewpoints over the Black Hills landscape.

Exploration began with local discovery of surface entrances in the late 19th and early 20th centuries and mapping has continued progressively since then; management focused on balancing public access with cave conservation and paleontological and speleological research. The monument has expanded mapping and protective measures as new passages were discovered over the 20th and 21st centuries.

The monument sits in the Black Hills of South Dakota, roughly northwest of Custer and east of the Black Hills National Forest; the nearest city with full services is Rapid City, about 60-70 miles to the northwest. The site is accessed by a park road off US Highway 16/385.

• Cave length and tours: More than 200 miles of passages have been surveyed, making it one of the longest caves in the world; most public access is by guided tours that follow developed paths and stairs.
• Visitor center and cave temperature: The visitor center sits above ground and includes exhibits and a scenic drive; cave temperatures remain near 50 degrees Fahrenheit year-round, so dress warmly for tours.