Hellhole

Hellhole
Pit entrance of Hellhole. Note caver visible at extreme bottom.
Location	Germany Valley, West Virginia
Depth	737 ft (225 m)
Length	42 m (67.5 km)
Discovery	1940s
Geology	New Market limestone
Entrances	1
Hazards	bat cave
Access	private

Hellhole is a large and deep pit cave in Germany Valley, eastern West Virginia. It is the 7th longest cave in the United States and is home to almost half of the world's population of Virginia big-eared bats. At 518 feet (158 meters), Hellhole is the deepest of several caves in the Valley.

Hellhole has had a long and storied association with the National Speleological Society dating back to the creation of that organization in the early 1940s. Many basic caving techniques (e.g., the single rope technique) were developed in Hellhole's 154-foot (47 meter) entrance drop.

The only known entrance to Hellhole is a funnel-shaped pit entrance on the lower slopes of North Fork Mountain. Descent by rope through this spectacular and storied 154-foot (47 m) entrance shaft gives access to a vast chamber. From the time exploration began there in the 1940s, cavers have documented over 41 miles (66 km) of mapped passage in the Hellhole system.

"Little Hellhole" is a well known pit deeper in the cave.

Hellhole's passages are developed predominantly in a layer of limestone known as the New Market. This same limestone is of remarkable commercial quality and is the primary object of the nearby Greer Lime Company open pit mining operations.

Hellhole is a hibernaculum site for two endangered and federally protected species of bats. For the Virginia big-eared bat (Corynorhinus townsendii virginianus), it is one of the largest hibernation sites in the world. There are estimated to be about 9,000 individuals in the cave, as against a total world population of about 20,000. Thus, Hellhole contains about 45% of the world's total population. The cave is the largest hibernation site in the mid-Atlantic region for the Indiana bat (Myotis sodalis). The cave contains about 9,000 of these as well, many more than any other cave in the region. In addition, the cave is one of the world’s three or four largest hibernation sites for Little brown bats (Myotis lucifugus), containing over 100,000 individual bats. Finally, the cave is also home to at least four other bat species.