Discovered by brothers Frank and Albert Michaud in 1900 as part of a mining claim, the cave's entrance was too small for human entry. The Michauds blew it open with dynamite and began exploring.
They discovered "crawlways and low-ceilinged rooms coated with beautiful calcite crystals that sparkled like 'jewels' in their lantern light," according to the Jewel Cave website. A local movement to set Jewel Cave aside for preservation culminated in the proclamation of the cave as a national monument by President Theodore Roosevelt on Feb. 7, 1908. The Michaud brothers eventually moved away and their family sold the claim to the government for about $750.
In May 1935, the Civilian Conservation Corps established a camp at Jewel Cave, located about 13 miles west of Custer. Twenty-five men, with a budget of $1,500, accomplished several projects for the National Park Service.
A three-room cabin and comfort stations were built. Sewage and water connections were completed for the cabin and public campground. The cave entrance was altered to provide easier access, and a surface trail of about 800 feet was constructed, along with a new stone stairway.
The Michaud's original log building was removed at this time.
In 1939, a National Park Service ranger was stationed at the monument and began conducting cave tours and providing visitor services. The cabin became home to the monument's first permanent ranger in 1941.
Except for a brief period of closure during World War II, National Park Service rangers staffed the cabin and cave tour operation.
In the late 1950s, significant discoveries were made within the cave, which led to development of a new visitor center and cave tour route.
Read more about recent discoveries at Jewel Cave on the Black Hills Knowledge Network.