Instruct: Given a question, retrieve relevant passages that can help answer the question.
Query: What's the deepest cave?
Krubera Cave (Georgian:კრუბერის გამოქვაბული or კრუბერის ღრმული, translit.:k'ruberis gamokvabuli or k'ruberis ghrmuli; Also known as Voronya Cave, sometimes spelled Voronja Cave) is the second deepest known cave on Earth after the Veryovkina Cave. It is located in the Arabika Massif of the Gagra Range of the Western Caucasus, in the Gagra district of Abkhazia,[note 1] a breakaway region of Georgia, currently under Russian occupation.[1][2]
Gourgouthakas (; from "small cutting on rocks, in which rain water is collected and from which animals drink water") is a cave located in the Lefka Ori mountains on the Greek island of Crete. It is the deepest cave in Greece, with an explored depth of , and is the 43rd deepest in the world.
The cave is the deepest known cave in Asia having been explored to a depth of from the entrance. At the lowest discovered level a water-filled siphon blocks further exploration. It is thought that the cave has the potential to be the deepest known cave in the world, with a theorised depth of making it deeper than the Veryovkina Cave. The explored length of the cave is .
Chevé Cave ( ; ) is a deep cave located in the Sierra Juárez mountain range in the southern Mexico state of Oaxaca. As of 2003, its deepest point has been measured at deep, making it the second deepest known cavern in the Western Hemisphere and the world’s 12th deepest cave. The cave's deepest known point is nearly one vertical mile and seven horizontal miles from the entrance, ending in a terminal sump. The present limit of exploration in Chevé, at 9.3 kilometers from the nearest entrance, represents one of the most remote locations ever attained inside any cave on Earth. The logistics of reaching this point are enormous: more than two kilometers of rope need to be rigged and three underground camps established. Chevé is the deepest proven freshwater hydrological system in the world. Temperatures in Chevé are moderate, ranging from . It has been most thoroughly explored under the leadership of caver Bill Stone.
The Park was established June 29, 2000 to protect Close To The Edge, a significant cave feature: the deepest shaft (255 m) and the third-deepest cave (472 m) in Canada. The cave was discovered in 1985, but its bottom was not reached until 2001. 
List of caves List of longest caves List of deepest caves Speleology– Science of cave and karst systems
The Hills conceal the largest underground river system in Britain; attempts to move from one cave to another through the underground rivers led to the development of cave diving in Britain. The first cave dive was attempted at Swildon's Hole in 1934, and the first successful dive was achieved the following year at Wookey Hole Caves, which has the deepest sump in Britain at 76 m (250 ft). The cave complexes at St. Dunstan's Well Catchment, Lamb Leer, and Priddy Caves have been identified as Sites of Special Scientific Interest.
The deepest cave in the Mendip Hills is Charterhouse Cave with a vertical range of .
Boybuloq Cave (also known as Boy Bulok) is a limestone cave in Uzbekistan and the deepest known cave in Asia. It is located high in the Gissar Range of mountains, near to Dehibolo, Uzbekistan's highest village. The cave and wider area is inaccessible for much of the year due to snow. Long-known to local people because of a nearby spring the cave was first explored by speleologists in 1984. Since then expeditions have mapped of passages in the cave and reached a total depth of . The cave could potentially extend much deeper and become the deepest in the world.
Jujar is deepest cave of Asia. in 7 September 2015 Jujar cave in eastern front of the Paraw recognized as deepest cave of Iran. an Iranian caving team consist of 24 athlete has discovered 806 meter and 8 centimeter of this cave. before this event Paraw cave (also located in this mount ) was deepest cave of Iran. in August 2016 an international expedition started to discover whole of the cave. eventually they announced that they successfully achieved to more than 1000 meter depth of the cave. thus Jujar became deepest cave of Asia and Iran.
Lamprechtsofen (also called Lamprechtshöhle or, together with a connected cave, Lamprechtsofen-Vogelschacht) is a limestone karst river cave in Austria. With a depth of , it is one of the deepest caves in the world. Before the discovery of the Krubera Cave in Georgia, it was the deepest-known cave in the world. Lamprechtsofen is located northwest of Weißbach bei Lofer (Salzburg), Austria, in the Leogang Mountains.
The Gouffre Berger is a French cave discovered on 24 May 1953 by Joseph Berger, Bouvet, Ruiz de Arcaute and Marc Jouffray. From 1953 to 1963, it was regarded as the deepest cave in the world at , relinquishing this title to the previous contender, Pierre Saint Martin, in 1964, after further exploration. The Gouffre Berger is now ranked 28th deepest cave in the world, and the 4th in France.
Ghar Parau is a limestone cave in the Zagros Mountains, north of Kermanshah in Western Iran. At 751 m deep, it is the deepest cave in Iran. Joujar Cave has been reported as the second deepest, at 568 m deep. 
Farr began caving in 1961 and cave diving in 1971, and within 10 years had established a world record for underwater cave penetration in the Bahamas. He is noted within the cave diving community for his explorations in Wookey Hole in 1977 and 1982, and for completing the first traverse of Llangattock Mountain in Wales in 1986, the execution of which was a televised media event, being the longest and deepest caving through trip in the British Isles. In 1978, Farr discovered also the Pollatoomary cave in the Partry Mountains of the Republic of Ireland. In 2008, his student Artur Kozłowski explored this cave to a depth of 103 metres, which made it the deepest known cave on the British Isles.
The Cave of Swallows, also called the Cave of the Swallows (), is an open air pit cave in the Municipality of Aquismón, San Luis Potosí, Mexico. The elliptical mouth, on a slope of karst, is 49 by 62 m wide and is undercut around all of its perimeter, widening to a room approximately 303 by 135 meters (994 by 442 ft) wide. The floor of the cave is a 333-meter (1092 ft) freefall drop from the lowest side of the opening, with a 370-meter (1,214 ft) drop from the highest side, making it the largest known cave shaft in the world, the second deepest pit in Mexico and perhaps the 11th deepest in the world.
There are hundreds of "holes" on Velebit. It has the largest and deepest caves in Croatia. The three-part "Lukina jama" cave is 1392 m deep, making it one of the deepest caves in the world, and the deepest in southeast Europe, while the "Slovačka jama" is 1320 m. What makes it unique is that it is completely vertical, steepest in the world. At the bottom of the pothole is a water course or siphon with branches that are still unexplored. A kind of leech was discovered in the pothole, which has been ascertained to represent a new species, genus and family; it has been named "Erpobdella mestrovi".
Charles William Steele, Jr. (born October 17, 1948), known as “Bill Steele,” is a cave explorer. He is a speleologist who has led and participated in expeditions to many of the longest and deepest caves in the USA, Mexico, and China. He has explored more than 2,500 caves across North America and Asia and has written two books chronicling his expeditions: "Yochib: The River Cave", and "Huautla: Thirty Years in One of the World's Deepest Caves.” TV shows such as National Geographic Explorer, NOVA and How’d They Do That? have aired programs on his expeditions.
Because the tectonic plates in this region are always moving and bumping into each other, the mountains are still rising and moving up. The rivers continue to cut into the bottom of the mountain, carving new caves over time. Hence, the river caves that are at a lower elevation are much younger than the higher, dry caves as they were more recently created. The river caves in this system such as Ken Cave and Tu Lan Cave are very young, only about 3 million years old. The higher, dry caves (dry Tu Lan and Ton Cave) are much older, and date around 5 million years old.
The French scientist Pierre G commented: "Tu Lan Cave System have the largest, deepest, longest, highest with many of connecting caves including inactive dry caves & active wet caves; including a number of natural phenomena such as the deepest Karst Doline of Southeast Asia (with a depth of more than 255m) and the habitat, stunning natural wonders, the majestic, unique of tropical jungle on the 400 million years of limestone."
This list of deepest mines includes operational and non-operational mines that are at least , which is the depth of Veryovkina Cave, the deepest known natural cave in the world. The depth measurements in this list represent the difference in elevation from the entrance of the mine to the deepest excavated point.
The Abismo Guy Collet (SP-090) is the deepest cave in South America, and the deepest in the world that is formed in quartzite. Located in a tepui in northern Brazil near the border with Venezuela, this cave was first explored by cavers in 2006 to a depth of 671 meters.
Specimens of "Zospeum tholussum" were recovered by a team of cavers and biologists of the Croatian Biospeleological Society (Hrvatsko Biospeleološko Društvo or HBSD) from the Lukina jama–Trojama cave system in the Velebit mountains of Croatia, during an expedition from July 29 to August 8, 2012. The cave system is the deepest in Croatia and one of the top twenty deepest caves in the world at a total measured depth of , including submerged passages. Aside from its great depth, the cave system is also known for its vertical orientation and deep shafts.
The difference in elevation of the cave's entrance and its deepest explored point is 2,197±20 metres (7,208±66ft). It became the deepest-known cave in the world in 2001 when the expedition of the Ukrainian Speleological Association reached a depth of 1,710m (5,610ft) which exceeded the depth of the previous deepest-known cave, Lamprechtsofen, in the Austrian Alps, by 80 metres (260ft). In 2004, for the first time in the history of speleology, the Ukrainian Speleological Association expedition reached a depth greater than 2,000 metres (6,600ft), and explored the cave to −2,080m (−6,824ft). Ukrainian diver Gennadiy Samokhin extended the cave by diving in the terminal sump to 46 metres' depth in 2007 and then to 52m in 2012, setting successive world records of 2,191m and 2,197m, respectively.[3][4] Krubera is one of the two known caves on Earth deeper than 2,000 metres.
Ellison's Cave is a pit cave located in Walker County, on Pigeon Mountain in the Appalachian Plateaus of Northwest Georgia. It is the 12th deepest cave in the United States and features the deepest, unobstructed pit in the continental US named Fantastic Pit. The cave is over 12 miles long and extends 1063 feet vertically.
GB Cave is a cave between Charterhouse and Shipham in the limestone of the Mendip Hills, in Somerset, England, and is close to Charterhouse Cave, the deepest in the region.
In January 2001, the Ukr.S.A. expedition explored the cave to −1,710m (−5,610ft) making it the deepest cave in the world. For the first time in the history of speleology, the deepest cave in the world had been established outside of western Europe. Since 2001, the Krubera explorations by the Ukr.S.A. have been undertaken within the frame of the multi-year project named "The Call of the Abyss", coordinated by A.Klimchuk, Y.Kasyan, G.Samokhin and K.Markovskoy. Besides the Ukrainian speleologists, cavers from many countries such as France, Spain, Russia, Moldova, Bulgaria, United Kingdom, Ireland, Israel and Lithuania have taken part in different expeditions of the Ukr.S.A.
In 1957, the discovery of Harwood's Hole in the South Island was to fully establish New Zealand as a country with extremely promising cave systems, and the cave with its 183 metre deep vertical entry shaft, and its passages extending for many hundreds of meters into the depths, was for a long time the deepest and most famous non-commercial cave in New Zealand. The area around Nelson also contains most of New Zealand's deepest caves (most discovered in the following decades), including Bulmer Cavern, a 70 km long cave system.