Limestone labyrinth[edit]
Mammoth Cave developed in thick Mississippian-aged limestone strata capped by a layer of sandstone, making the system remarkably stable. It is known to include more than 390 miles (630 km) of passageway;[5] new discoveries and connections add several miles to this figure each year. Mammoth Cave National Park was established to preserve the cave system.
The upper sandstone member is known as the Big Clifty Sandstone: thin, sparse layers of limestone interspersed within the sandstones give rise to an epikarstic zone, in which tiny conduits (cave passages too small to enter) are dissolved by the natural acidity of groundwater. The epikarstic zone concentrates local flows of runoff into high-elevation springs which emerge at the edges of ridges. The resurgent water from these springs typically flows briefly on the surface before sinking underground again at elevation of the contact between the sandstone caprock and the underlying massive limestones. It is in these underlying massive limestone layers that the human-explorable caves of the region have naturally developed.
The limestone layers of the stratigraphic column beneath the Big Clifty, in increasing order of depth below the ridgetops, are the Girkin Formation, the Ste. Genevieve Limestone, and the St. Louis Limestone. For example, the large Main Cave passage seen on the Historic Tour is located at the bottom of the Girkin and the top of the Ste. Genevieve Formation.
The Bottomless Pit in Mammoth Cave, woodcut, 1887 (Nuno Carvalho de Sousa Collection, Lisbon)
Each of the primary layers of limestone is divided further into named geological units and subunits. One area of cave research involves correlating the stratigraphy with the cave survey produced by explorers. This makes it possible to produce approximate three-dimensional maps of the contours of the various layer boundaries without the necessity for test wells and extracting core samples.
The upper sandstone caprock is relatively hard for water to penetrate: the exceptions are where vertical cracks occur. This protective role means that many of the older, upper passages of the cave system are very dry, with no stalactites, stalagmites, or other formations which require flowing or dripping water to develop.
However, the sandstone caprock layer has been dissolved and eroded at many locations within the park, such as the Frozen Niagara room. The "contact" between limestone and sandstone can be found by hiking from the valley bottoms to the ridgetops: typically, as one approaches the top of a ridge, one sees the outcrops of exposed rock change in composition from limestone to sandstone at a well-defined elevation.[6]
At one valley bottom in the southern region of the park, a massive sinkhole has developed. Known as "Cedar Sink," the sinkhole features a small river entering one side and disappearing back underground at the other side.
Mammoth Cave is home to the endangered Kentucky cave shrimp, a sightless albino shrimp.
Visiting[edit]
A ranger-guided tour of the cave
The National Park Service offers several cave tours to visitors. Some notable features of the cave, such as Grand Avenue, Frozen Niagara, and Fat Man's Misery, can be seen on lighted tours ranging from one to six hours in length. Two tours, lit only by visitor-carried paraffin lamps, are popular alternatives to the electric-lit routes. Several "wild" tours venture away from the developed parts of the cave into muddy crawls and dusty tunnels. The lectures delivered by the National Park Service cave guides are varied by tour, so that in taking several tours the visitor learns about different facets of the cave's formation, or of the cave's human history and prehistory.
The Echo River Tour, one of the cave's most famous attractions, used to take visitors on a boat ride along an underground river. The tour was discontinued for logistic and environmental reasons in the early 1990s.[7]
Mammoth Cave headquarters and visitor's center is located on Mammoth Cave Parkway. The parkway connects with Kentucky Route 70 from the north and Kentucky Route 255 from the south within the park.[8]
History[edit]
Prehistory[edit]
The World Heritage Site plaque
The story of human beings in relation to Mammoth Cave spans six thousand years. Several sets of Native American remains have been recovered from Mammoth Cave, or other nearby caves in the region, in both the 19th and 20th centuries. Most mummies found represent examples of intentional burial, with ample evidence of pre-Columbian funerary practice.
An exception to purposeful burial was discovered when in 1935 the remains of an adult male were discovered under a large boulder. The boulder had shifted and settled onto the victim, a pre-Columbian miner, who had disturbed the rubble supporting it. The remains of the ancient victim were named "Lost John" and exhibited to the public into the 1970s, when they were interred in a secret location in Mammoth Cave for reasons of preservation as well as emerging political sensitivities with respect to the public display of Native American remains.
Research beginning in the late 1950s led by Patty Jo Watson of Washington University in St. Louis, Missouri has done much to illuminate the lives of the late Archaic and early Woodland peoples who explored and exploited caves in the region. Preserved by the constant cave environment, dietary evidence yielded carbon dates enabling Watson and others to determine the age of the specimens, and an analysis of their content, also pioneered by Watson, allows determination of the relative content of plant and meat in the diet of either culture over a period spanning several thousand years. This analysis indicates a timed transition from a hunter-gatherer culture to plant domestication and agriculture.
Another technique employed in archaeological research at Mammoth Cave was "experimental archaeology", in which modern explorers were sent into the cave using the same technology as that employed by the ancient cultures whose leftover implements lie discarded in many parts of the cave. The goal was to gain insight into the problems faced by the ancient people who explored the cave, by placing the researchers in a similar physical situation.
Ancient human remains and artifacts within the caves are protected by various federal and state laws. One of the most basic facts to be determined about a newly discovered artifact is its precise location and situation. Even slightly moving a prehistoric artifact contaminates it from a research perspective. Explorers are properly trained not to disturb archaeological evidence, and some areas of the cave remain out-of-bounds for even seasoned explorers, unless the subject of the trip is archaeological research on that area.
Besides the remains that have been discovered in the portion of the cave accessible through the Historic Entrance of Mammoth Cave, the remains of cane torches used by Native Americans, as well as other artifacts such as drawings, gourd fragments, and woven grass moccasin slippers are found in the Salts Cave section of the system in Flint Ridge.
Earliest known history[edit]
The 31,000-acre (13,000 ha) tract known as the "Pollard Survey" was sold by indenture September 10, 1791 in Philadelphia by William Pollard. 19,897 acres (8,052 ha) of the "Pollard Survey" between the North bank of Bacon Creek and the Green River were purchased by Thomas Lang, Jr., a British American merchant from Yorkshire, England on June 3, 1796, for £4,116/13s/0d (£4,116.65). The land was lost to a local county tax claim during the War of 1812.
Legend has it that the first European to discover Mammoth Cave was either John Houchin or his brother Francis Houchin, in 1797. While hunting, Houchin pursued a wounded bear to the cave's large entrance opening near the Green River. Some Houchin Family tales have John Decatur "Johnny Dick" Houchin as the discoverer of the cave, but this is highly unlikely because Johnny Dick was only 10 years old in 1797 and was unlikely to be out hunting bears at such a tender age. His father John is the more likely candidate from that branch of the family tree, but the most probable candidate for discoverer of Mammoth Cave is Francis "Frank" Houchin whose land was much closer to the cave entrance than his brother John's. There is also the argument that their brother Charles Houchin, who was known as a great hunter and trapper, was the man who shot that bear and chased it into the cave. The shadow over Charles's claim is the fact that he was residing in Illinois until 1801. Contrary to this story is Brucker and Watson's The Longest Cave, which asserts that the cave was "certainly known before that time." Caves in the area were known before the discovery of the entrance to Mammoth Cave. Even Francis Houchin had a cave entrance on his land very near the bend in the Green River known as the Turnhole, which is less than a mile from the main entrance of Mammoth Cave.
The land containing this historic entrance was first surveyed and registered in 1798 under the name of Valentine Simons. Simons began exploiting Mammoth Cave for its saltpeter reserves.
According to family records passed down through the Houchin, and later Henderson families, John Houchin was bear hunting and the bear turned and began to chase him. He found the cave entrance when he ran into the cave for protection from the charging bear.
19th century[edit]
Map of Mammoth Cave from 1897, penned by R. E: Call
In partnership with Valentine Simon, various other individuals would own the land through the War of 1812, when Mammoth Cave's saltpeter reserves became significant due to the British blockade of United States's ports. The blockade starved the American military of saltpeter and therefore gunpowder. As a result, the domestic price of saltpeter rose and production based on nitrates extracted from caves such as Mammoth Cave became more lucrative.
In July 1812, the cave was purchase