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.
A stalactite is a mineral formation that hangs from the ceiling of caves, hot springs, or man-made structures such as bridges and mines. Any material that is soluble and that can be deposited as a colloid, or is in suspension, or is capable of being melted, may form a stalactite. Stalactites may be composed of lava, minerals, mud, peat, pitch, sand, sinter, and amberat. A stalactite is not necessarily a speleothem, though speleothems are the most common form of stalactite because of the abundance of limestone 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.
Cave-diving is underwater diving in water-filled caves. It may be done as an extreme sport, a way of exploring flooded caves for scientific investigation, or for the search for and recovery of divers or, as in the 2018 Thai cave rescue, other cave users. The equipment used varies depending on the circumstances, and ranges from breath hold to surface supplied, but almost all cave-diving is done using scuba equipment, often in specialised configurations with redundancies such as sidemount or backmounted twinset. Recreational cave-diving is generally considered to be a type of technical diving due to the lack of a free surface during large parts of the dive, and often involves planned decompression stops. A distinction is made by recreational diver training agencies between cave-diving and cavern-diving, where cavern diving is deemed to be diving in those parts of a cave where the exit to open water can be seen by natural light. An arbitrary distance limit to the open water surface may also be specified.
Oregon Caves National Monument and Preserve is a protected area in the northern Siskiyou Mountains of southwestern Oregon in the United States. The 4,554-acre (1,843 ha) park, including the marble cave, is 20 miles (32 km) east of Cave Junction, on Oregon Route 46. The protected area, managed by the National Park Service (NPS), is in southwestern Josephine County, near the Oregon–California border.
Wind Cave National Park is an American national park located 10 miles (16 km) north of the town of Hot Springs in western South Dakota. Established on January 3, 1903 by President Theodore Roosevelt, it was the sixth national park in the U.S. and the first cave to be designated a national park anywhere in the world. The cave is notable for its calcite formations known as boxwork, as well as its frostwork. Approximately 95 percent of the world's discovered boxwork formations are found in Wind Cave.
Jewel Cave National Monument contains Jewel Cave, currently the fifth longest cave in the world and second longest cave in the United States, with 219.66 miles (353.51 km) of mapped passageways. 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.
In geology, a blowhole or marine geyser is formed as sea caves grow landward and upward into vertical shafts and expose themselves toward the surface, which can result in hydraulic compression of seawater that is released through a port from the top of the blowhole. The geometry of the cave and blowhole along with tide levels and swell conditions determine the height of the spray.
The Gunung Mulu National Park is a national park in Miri Division, Sarawak, Malaysia. It is a UNESCO World Heritage Site that encompasses caves and karst formations in a mountainous equatorial rainforest setting. The park is famous for its caves and the expeditions that have been mounted to explore them and their surrounding rainforest, most notably the Royal Geographical Society Expedition of 1977–1978, which saw over 100 scientists in the field for 15 months. This initiated a series of over 20 expeditions now named the Mulu Caves Project.
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.
In geology, frostwork is a type of speleothem with acicular ("needle-like") growths almost always composed of aragonite or calcite replaced aragonite. It is a variety of anthodite. Frostwork can also be made of opal or gypsum. In some caves frostwork may grow on top of cave popcorn or boxwork.
A solutional cave, solution cave, or karst cave is a cave usually formed in the soluble rock limestone. It is the most frequently occurring type of cave. It can also form in other rocks, including chalk, dolomite, marble, salt beds, and gypsum.
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.
Jan H. Conn and Herbert William Conn were climbing and caving pioneers. They are credited with establishing many classic climbs in areas like Carderock in Maryland, Seneca Rocks in West Virginia, Cannon Cliff in New Hampshire and Black Hills of South Dakota. They are also well known as cave explorers who in the 1960s and 1970s discovered and mapped over 60 miles of Jewel Cave, making it the world’s third-longest cave system.
The Pahasapa Formation is a geological unit of primarily limestone and dolomite that is exposed in the Black Hills of South Dakota and northeastern Wyoming, and underlies parts of Nebraska, in the United States. Also referred to as the Pahasapa Limestone, this unit is analogous to the Madison Limestone, the Lodgepole Limestone, and the Burlington Limestone, other Mississippian-aged limestones and dolomites in the midwestern United States. Some recent literature has grouped stretches of the Pahasapa into the Madison Group. The formation is of local importance, as it contains the Madison aquifer, and two of the ten longest caves in the world.
Pınargözü Cave, is a cave 18 kilometres (11 mi) west of the town of Yenişarbademli in Isparta Province, Turkey. It is considered the longest cave in Turkey, although it has not yet been fully explored, and the precise extent to which it has been explored is in dispute.
Patricia Kambesis is an American caver, cartographer and educator.
