Jewel Cave Centennial Jewel Cave National Monument Celebrates 100 Years!
On February 7, 1908, President Theodore Roosevelt signed a proclamation that established Jewel Cave National Monument under the authority of the 1906 Antiquities Act. This created the Monument as part of the National Park System to protect the small, but extraordinarily beautiful cave, which became known for the jewel-like calcite crystals that line the cave walls. One hundred years later, exploration has revealed Jewel Cave to be the second longest cave in the world with a current length of over 141 miles. Exploration continues to reveal the hidden miles of passages, beneath the Black Hills, with a variety of amazing cave formations.