Wookey Hole Caves are a series of limestone caverns, a show cave and tourist attraction in the village of Wookey Hole on the southern edge of the Mendip Hills near Wells in Somerset, England. The River Axe flows through the cave. It is a Site of Special Scientific Interest (SSSI) for both biological and geological reasons. Wookey Hole cave is a "solutional cave", one that is formed by a process of weathering in which the natural acid in groundwater dissolves the rocks. Some water originates as rain that flows into streams on impervious rocks on the plateau before sinking at the limestone boundary into cave systems such as Swildon's Hole, Eastwater Cavern and St Cuthbert's Swallet; the rest is rain that percolates directly through the limestone. The temperature in the caves is a constant 11 °C (52 °F).
Gaping Gill is a natural cave in North Yorkshire, England. It is one of the unmistakable landmarks on the southern slopes of Ingleborough – a 98-metre (322 ft) deep pothole with the stream Fell Beck flowing into it. After falling through one of the largest known underground chambers in Britain, the water disappears into the bouldery floor and eventually resurges adjacent to Ingleborough Cave.
Swildon's Hole is an extensive cave in Priddy, Somerset. At 9,144 metres (30,000 ft) in length, it is the longest cave on the Mendip Hills. It has been found to be connected to Priddy Green Sink and forms part of the Priddy Caves Site of Special Scientific Interest (SSSI).
Nettlebed Cave is a limestone cave located in the Mount Arthur region of the northwest South Island of New Zealand. The presence of ongaonga, an endemic tree nettle, near the bottom entrance gives the cave its name.
The Cave Diving Group (CDG) is a United Kingdom-based diver training organisation specialising in cave diving.
Dan yr Ogof, at the National Showcaves Centre for Wales, is a 17-kilometre (11 mi) long cave system in south Wales, about 5 miles (8 km) north of Ystradgynlais and 15 miles (24 km) southwest of Brecon, in the Brecon Beacons National Park. It is the main feature of a show cave complex, which is claimed to be the largest in the United Kingdom and is a tourist attraction in Wales. The first section of the cave system is open to the public, but the extensive cave system beyond is scheduled as a national nature reserve and is open only to bona fide cavers.
Craighead Caverns is an extensive cave system located in between Sweetwater and Madisonville, Tennessee. It is best known for containing the United States' largest and the world's second largest non-subglacial underground lake, The Lost Sea. In addition to the lake, the caverns contain an abundance of crystal clusters called anthodites, stalactites, stalagmites, and a waterfall.
The cave catfish is a critically endangered species of airbreathing catfish. This cavefish is only known to live in the Aigamas cave, Otjozondjupa region, Namibia. It has also been reported from the nearby Dragon's Breath Cave. The golden cave catfish lack pigmentation and are up to 16.1 cm in standard length. They have very small eyes that are covered with skin, and are probably effectively blind. They feed on detritus and invertebrates that fall into the lake in which they live. The population is estimated at 200–400 individuals. Little is known about its reproduction, and attempts to breed it in captivity have failed. The population is threatened by chance events and water extraction from the cave lake, which has resulted in a drop of the water level.
Recreational caving in the United Kingdom dates back to the mid-19th century. The four major caving areas of the United Kingdom are North Yorkshire, South Wales, Derbyshire, and the Mendips. Minor areas include Devon, North Wales, and the Scottish Highlands.
An underground lake or subterranean lake is a lake underneath the surface of the Earth. Most naturally occurring underground lakes are found in areas of karst topography, where limestone or other soluble rock has been weathered away, leaving a cave where water can flow and accumulate.
The Blue Hole of Santa Rosa, or simply the Blue Hole, is a circular, bell-shaped pool or small lake located along Route 66 east of Santa Rosa, New Mexico that is a tourist attraction and swimming venue, and one of the most popular dive destinations in the US for scuba diving and training. The Blue Hole is an artesian well and cenote that was once used as a fish hatchery.
Noon's Hole lies about 5 km northwest of the centre of Boho, in the townland of Old Barr in the parish of Devenish, County Fermanagh, close to the border with Boho parish. The cave is under part of the escarpment on the east side of the Glenade Sandstone uplands. At 81 m (266 ft), this pothole was thought to have the deepest shaft in Ireland, but this honour was passed to the nearby Reyfad Pot, which contains an entrance shaft of 88 m (289 ft). The continuation of the cave system contains 3.7 km (2.3 mi) of passage, and it connects to the resurgence at Arch Cave through three cave dives, making this system the 8th deepest in Ireland, at 108 m (354 ft).
Martyn Farr is a leading exploratory cave diver and caver, known for his record-breaking cave dives and the exploration of many miles of previously undiscovered underground passages. As an author and photographer he has written many books on the subject of cave diving history and techniques and caving locations.
Pollatoomary is the deepest explored underwater cave in Ireland. It has been explored to an underwater depth of 113 metres (371 ft). The explored limit of Pollatoomary is also 23 metres (75 ft) deeper underwater than that of the terminal sump in Wookey Hole Caves in Somerset, England, which previously held the record for the deepest underwater cave in Britain and Ireland.
Dragon's breath comes from mythology, as used to describe the ability of dragons to emit fire from their mouth.
Namibia, a country in south-western Africa, has a total of 124 known caves, 41 of which are situated in the Otjozondjupa Region.
Orda Cave is a gypsum crystal cave found underneath the western Ural Mountains. The mouth is near the shore of the Kungur River just outside Orda, Perm Krai in Russia. The cave system stretches over 5.1 kilometres (3.2 mi) with around 4.8 kilometres (3.0 mi) over the overall length being under water. This makes it one of the longest underwater caves and the largest underwater gypsum cave in the world. It contains the longest siphon in the former Soviet Union.
The Underground Eiger is a made-for-television documentary that was released in 1979. It details a world record-breaking cave dive of 6,000 ft (1,800 m) made by Geoff Yeadon and Oliver Statham from West Kingsdale Master Cave, in North Yorkshire, England to Keld Head. An estimated 20 million viewers watched its television debut. It has been called "legendary in caving folklore," and notable cave diver Rick Stanton cites it as the impetus that sparked his interest in cave diving.
Penelope Powell was a pioneering cave diver. She was Diver No. 2 for the first successful cave dive using breathing equipment in Britain at Wookey Hole Caves in the Mendip Hills, Somerset on 18 August 1935. Powell was posthumously entered into the Women Divers Hall of Fame (WDHOF) in 2023.
