President Theodore Roosevelt proclaimed Jewel Cave a National Monument on February 7, 1908.

Jewel Cave was formed by the gradual dissolution of limestone by stagnant, acid-rich water.

Finally, Jewel Cave contains a very rare formation called a hydromagnesite balloon.

Jewel Cave is open year round.

(describes the exploration of Jewel Cave from its discovery to the mid-1980s)

It travels near Jewel Cave, the second-longest cave in the world.

Jewel Cave (2nd Longest Cave in the World)

The most dramatic subterranean environment in the Black Hills is Jewel Cave.

Tourists began to flock to the cave to see its eerie formations, and in 1908, Jewel Cave was proclaimed a national monument.

Jewel Cave's park service companion, Wind Cave, is best known for its boxwork formations and its scenic, 44-square-mile above-ground national park.