How to Use the Context
Mammoth Cave enjoys the distinction of being the longest cave in the world, with more than 345 miles of explored passageways. In 1981 the United Nations Educational Scientific and Cultural Organization (UNESCO) recognized it as a World Heritage Site and in 1990 as an International Biosphere Reserve. The cave is particularly interesting because the processes that formed it in the first place are continuing. Passageways are being carved out today in the same way as they have been for more than a million years.
Mammoth Cave National Park’s surface area of 52,830 acres is characterized by rugged forested hills, high rocky bluffs, and two major rivers, the Green and the Nolin. This serene and largely unpopulated natural setting in Kentucky belies the long and colorful history of the area. Mammoth Cave is the centerpiece of one of the greatest cave regions in the world. The Mammoth Cave area includes numerous deep cracks, sinkholes, underground streams, and layers of limestone rock. These rock layers are eroded and dissolved by underground water. The water drains underground through vertical cracks and horizontally between layers of limestone and eventually forms sinkholes and caves. The resulting landscape, created by the action of water, is known as a karst landscape. Underground water has carved out Mammoth Cave in long, horizontal passageways over the past several million years. The upper passages, dry today, were hollowed out millions of years ago; the lower passages are still being enlarged by the flowing waters of Echo River and several other underground streams. Mammoth Cave’s huge vertical shafts, called pits and domes, have been created by groundwater seeping downward through sinkholes or cracks located beyond the edge of the protective hard layer of sandstone that overlies much of the cave.
Water also has been essential in decorating parts of the cave with gypsum formations, stalactites, stalagmites, draperies and flowstone. The delicate gypsum formations occur in some of the cave’s drier chambers; the rest of the formations appear in some of the wetter chambers.
Water is also vital to the unusual biota, or animal and plant life, of the region. Above ground and in the cave there are approximately 1,000 kinds of plants and about 500 types of animals. The cave itself abounds with unusual fish, shrimp, crayfish, crickets, spiders, beetles, molds, and mushrooms that live within its cool darkness. Many cave animals, like the blindfish and certain crickets, are blind. Some do not even have eyes. Other animal and plant life lack skin pigments and appear to be entirely white. Both the sightless and the colorless creatures would be unable to survive in the surface environment. They depend on the clean water of unpolluted underground streams to carry their food to them.
Geologists, zoologists, ecologists, archeologists, historians, spelunkers, and ordinary citizens are amazed and thrilled by the size, complexity of history, and environment of Mammoth Cave.