Mammoth Cave National Park is an area in south-central Kentucky, centered around Mammoth Cave, the most extensive cave system known in the world. It was established as a National park on July 1, 1941. It became a World Heritage Site on October 27, 1981, and an international Biosphere Reserve on September 26, 1990.
The park's 52,830 acres (about 21,390 hectares) is located in Edmonson County, Kentucky, with small areas extending eastward into Hart County and Barren County. It is centered around the Green River, with a tributary, the Nolin River, feeding into the Green just inside the park. Almost two million people visit the park every year.
Mammoth Cave is a system in thick limestone strata capped by a layer of sandstone, making the system remarkably stable. It comprises over 336 miles of passageway. The cave was a significant source for saltpeter production for the manufacture of gunpowder at one time, especially in the War of 1812.
Mammoth Cave was mapped and named extensively by Steven Bishop, a slave guide to the cave during the 1840s and 1850s.
The cave is linked with computer games: part of it, the Bedquilt Cave, was the stage for one of the first computer games ever, Adventure (the precursor to all adventure games).
See also: Biosphere Reserves in the United States of America, List of Conservation topics
