Mammoth Cave National Park

Mammoth Cave National Park covers 52,007 acres of south-central Kentucky, mostly in Edmonson County, and the Green River runs through it. The cave system, officially the Mammoth-Flint Ridge Cave System since a connection was found in 1972, has more than 426 surveyed miles of passages, over one and a half times the length of the next longest cave. New discoveries add several miles each year.

The cave formed about 330 million years ago in thick Mississippian limestone capped by a layer of sandstone, which keeps the system remarkably stable. Because the sandstone sheds water, many of the older upper passages are dry and have no stalactites or stalagmites. The park was established on July 1, 1941, became a World Heritage Site in 1981 and was named an International Dark Sky Park in 2021.

People have been in Mammoth Cave for at least five thousand years. Cane torches, drawings and woven grass slippers left by Native Americans survive in the Salts Cave section, and ancient remains and artifacts are protected by law. In 1798 the land around the historic entrance was registered, and the cave was mined for saltpeter. During the War of 1812 the work became industrial, using a labor force of about 70 enslaved people.

After the war the cave turned into a tourist attraction. Franklin Gorin, who bought it in 1838, used enslaved people as guides. One of them, Stephen Bishop, explored the cave extensively in the 1840s and 1850s and became one of its most celebrated figures. The National Park Service offers tours that visit features such as Grand Avenue, Frozen Niagara and Fat Man's Misery, including two lit only by visitor-carried lamps.