Mammoth Cave National Park is located in Cave City, Kentucky, and is the longest known cave in the world. The official name of Mammoth Park is the Mammoth-Flint National Cave System, named for the ridge under which the cave is formed. Mammoth Cave was established as a national park on July 1st, 1941 and on October 27th, 1981, it was listed as a World Heritage Site. The park was listed as an international Biosphere Region on September 26th, 1990.
Mammoth Cave National Park consists of 52,830 acres in Edmondson County, Kentucky with smaller areas extending east into Hart and Barren Counties. The park is centered on the Green River, with a tributary, the Nolin River which feeds the Green River just inside the park. The Green River is damned up near the west border of the park, and because of this, only a small section of the river flows freely in the park.
The cave is composed of Mississippian-aged limestone strata, which are capped off by a layer of sandstone. The cave has more than 360 miles of passageways, and every year new discoveries and several miles increase the length. The upper sandstone layer is known as the Big Clifty Sandstone, which are thin, interspersed layers containing sandstone and tiny conduits, too small to enter. The Main Cave on the lower level is located at the bottom of the Girkin Formation and the St. Genevieve Layer.
Each layer of limestone is divided into further named units and subunits. The older, upper passageways of the cave are dry and have no stalagmites or stalactites, which are formations made by dripping water. The contact between the limestone and sandstone can be witnessed by hiking through the valley up to the ridge tops. Cedar Sink is a large sinkhole at the bottom of a valley in the south region of the park, the sinkhole features a small river on one side and a disappearing bank on the other side.
The Mammoth Cave National Park is overseen by the National Park System, and offers many services to guests. Some of the most famous features of the cave such as Grand Avenue, Frozen Niagara and Fat Mans Misery, can be visited by lighted guided tours that last from one to six hours in duration. The park also offers two tours which are lighted only by guests carrying paraffin-lit torches. There are also tours offered that venture away from typical areas, and offer guests the chance to explore through muddy crawl spaces and dusty trails in undeveloped areas of the cave system.
Mammoth Cave National Park tours are unique in that each one is part of an interpretive program, and has graphics and artifacts on display throughout the cave. Many of the tour guides include a theatrical component, which provides entertaining presentations for visitors. Mammoth Cave contains an underground labyrinth of caves, and beautiful rolling hills and valleys above ground, visitors can enjoy hiking, picnicking, horseback riding, camping and many more activities. The park and cave system welcomes an estimated 500,000 people annually who flock to enjoy all it has to offer.