Chevé Cave
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.
Martyn Farr
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.