The following is a list of the longest caves in the United States per length (> 50 km) of documented passageways. Many passageways are still being discovered; this list is based on the latest verifiable data. [1]
The following is a list of the longest caves in the United States per length (> 50 km) of documented passageways. Many passageways are still being discovered; this list is based on the latest verifiable data. [1]
A cave or cavern is a natural void in the ground, specifically a space large enough for a human to enter. Caves often form by the weathering of rock and often extend deep underground. The word cave can refer to smaller openings such as sea caves, rock shelters, and grottos, that extend a relatively short distance into the rock and they are called exogene caves. Caves which extend further underground than the opening is wide are called endogene caves.
Mammoth Cave National Park is a national park in south-central Kentucky, encompassing portions of Mammoth Cave, the longest cave system known in the world. The park's 52,830 acres (21,380 ha) are located primarily in Edmonson County, with small areas extending eastward into Hart and Barren counties. The Green River runs through the park, with a tributary called the Nolin River feeding into the Green just inside the park.
Speleology is the scientific study of caves and other karst features, as well as their composition, structure, physical properties, history, ecology, and the processes by which they form (speleogenesis) and change over time (speleomorphology). The term speleology is also sometimes applied to the recreational activity of exploring caves, but this is more properly known as caving, potholing, or spelunking. Speleology and caving are often connected, as the physical skills required for in situ study are the same.
Jewel Cave National Monument contains Jewel Cave, currently the fifth longest cave in the world and second longest cave in the United States, with 219.77 miles (353.69 km) of mapped passageways as of March 2024. It is located approximately 13 miles (21 km) west of the town of Custer in Black Hills of South Dakota. It became a national monument in 1908.
At 150.4 miles (242.0 km), Lechuguilla Cave is the eighth-longest explored cave in the world and the second deepest in the continental United States. It is most famous for its unusual geology, rare formations, and pristine condition.
The Cave Research Foundation (CRF) is an American private, non-profit group dedicated to the exploration, research, and conservation of caves. The group arose in the early 1950s from the exploration efforts at Floyd Collins Crystal Cave, now within Mammoth Cave National Park. Its stated goals were: to promote exploration and documentation of caves and karst areas, initiate and support cave and karst research, aid in cave conservation and protection, and to assist with the interpretation of caves and karst to the public.
The Woodville Karst Plain Project or WKPP, is a project and organization that maps the underwater cave systems underlying the Woodville Karst Plain. This plain is a 450-square-mile (1,200 km2) area that runs from Tallahassee, Florida, U.S. to the Gulf of Mexico and includes numerous first magnitude springs, including Wakulla Springs, and the Leon Sinks Cave System, the longest underwater cave in the United States. The project grew out of a cave diving research and exploration group established in 1985 and incorporated in 1990.
Optymistychna is a gypsum cave located near the Ukrainian village of Korolivka, Chortkiv Raion, Ternopil Oblast. Approximately 264 km (164 mi) of passageways have been mapped within. As a result, it is the longest cave in Europe and the seventh-longest cave in the world, after Mammoth Cave, Sistema Sac Actun, Jewel Cave, Shuanghedong and Sistema Ox Bel Ha. It is also the longest gypsum cave in the world.
Carlsbad Caverns National Park is an American national park in the Guadalupe Mountains of southeastern New Mexico. The primary attraction of the park is the show cave Carlsbad Cavern. Visitors to the cave can hike in on their own via the natural entrance or take an elevator from the visitor center.
Sistema Sac Actun is an underwater cave system situated along the Caribbean coast of the Yucatán Peninsula with passages to the north and west of the city of Tulum. Discovery of a connection to Sistema Dos Ojos in 2018 made it the longest known underwater cave system. As of January 2023, it is the second longest underwater cave system in the world, only surpassed by Sistema Ox Bel Ha.
The Butler Cave Conservation Society (BCCS) is a 501(c)(3) non-profit Virginia corporation dedicated to the conservation, exploration, survey, preservation, and scientific study of the caves and karst in and around Burnsville Cove, Virginia.
Sistema Huautla is a cave system in the Sierra Mazateca mountains of the southern Mexican state of Oaxaca. As of April 2021 it is the deepest cave system in the Western Hemisphere, 1,560 metres (5,120 ft) from top to bottom, with over 55 miles of mapped passageways. It is the tenth deepest cave in the world. It is also the 26th longest cave system with over 100 km length.
Tears of the Turtle Cave is located in the Bob Marshall Wilderness in western Montana and is currently the deepest known limestone cave in the United States since passing New Mexico's Lechuguilla cave in 2014. As of August 2022, the cave is known to be 2,052 feet (625 m) deep and 1.488 miles (2,395 m) long. The cave consists mostly of narrow fissure passages passing over approximately 50 short rope drops. With a mean temperature of 37 °F (3 °C) it is muddy and poorly decorated.
The Fisher Ridge Cave System is a cave system located in Hart County, Kentucky, United States, near Mammoth Cave National Park. As of November 2019 it had been mapped to a length of 130.001 miles (209.216 km), making it the fifth-longest cave in the United States and the tenth-longest in the world.
Patricia Kambesis is an American caver, cartographer and educator.
Friars Hole Cave System is a cave in West Virginia's Greenbrier and Pocahontas counties. First surveyed in the 1960s, it is one of the longest in the United States and the world.
A breathing cave or barometric cave is a rare type of cave in which atmospheric pressure gradients between the inside and outside of a cave cause air to flow in to or out of the cave. The concept of air flowing through a cave is common, however in most caves this airflow is caused by a difference in temperature rather than air pressure; in barometric caves the thermal mechanism inside the cave is not great enough to cause such airflow. The speed of the airflow in barometric caves is directly correlated with the atmospheric pressure difference between the inside and outside of the cave. When the air pressure outside of the cave is higher than that inside the cave air blows into the cave and vice versa; if the air pressures are at equilibrium there is no airflow.