Craighead Caverns is an extensive cave system located in between Sweetwater and Madisonville, Tennessee. It is best known for containing the United States' largest and the world's second largest non-subglacial underground lake, The Lost Sea. In addition to the lake, the caverns contain an abundance of crystal clusters called anthodites, stalactites, stalagmites, and a waterfall. History Located in the foothills of the Great Smoky Mountains, the caverns are named after their former owner, a Cherokee Native American, Chief Craighead. The caverns were used by the Cherokee as a meeting place for their councils. During the American Civil War, the caves were mined by Confederate soldiers for saltpeter, a commodity necessary to the manufacture of gunpowder. The major cave and lake area was also used as a hideout for moonshiners, especially during the Prohibition era. In 1939, explorers found the fossilized remains of a Pleistocene jaguar. The persons who made the discovery were cave guides Jack Kyker and Clarence Hicks, who were exploring in the cave during their off hours. They reported their find to Dr. W. J. Cameron and W. E. Michael of Sweetwater, who then owned the cave. The owners submitted the bones to the American Museum of Natural History in New York City, where they were identified as bones of a very large jaguar and an elk fawn. George Gaylord Simpson, a vertebrate paleontologist at the museum, subsequently visited Craighead Caverns in May 1940. During his visit, he recovered additional jaguar bones and made casts of several jaguar footprints in the mud floor of the cave. His excavation and findings are reported in American Museum Novitates, No. 1131 (August 6, 1941) on pages 1–12. The report includes photographs of the bones and footprints. Simpson referred the fossils to the large Panthera onca augusta, at that time the remains from Craighead Caverns were some of the best known of the subspecies. A mushroom farm was operated in the cave from 1939 to 1940. The manure for this operation was supplied from Fort Oglethorpe, where many horses were stabled. The mushroom beds were located in the Big Room, a few hundred feet northeast of the historic entrance. In 1947, a wooden dance floor was built in this same area of the cave, and a nightclub, known as the "Cavern Tavern", was operated there. Craighead Caverns was added to the National Park Service list of National Natural Landmarks in 1974. The