Boesmansgat
Boesmansgat, also known in English as "Bushman's Hole", is a deep submerged freshwater cave (or sinkhole) in the Northern Cape province of South Africa, which has been dived to a depth of 282.6 metres (927 ft).
Boesmansgat was believed to have first been explored by amateur diver Mike Rathbourne, in 1977. The greatest depth attained was by Nuno Gomes, in 1996. Its altitude of over 1,500 metres (4,921 ft) makes this a particularly challenging dive, requiring a decompression schedule equivalent for a dive to 339 metres (1,112 ft) feet at sea level. (Gomes' dive was a close call, as he got stuck in the mud on the bottom of Bushman's Hole for two minutes before escaping.)
On 24 November 2004, Verna van Schaik set the Guinness Woman's World Record for the deepest dive with a dive to 221 metres (725 ft).
In Mo Hayder's novel Ritual (2008), the death of the parents of one of the protagonists while diving in Bushman's Hole is an important plot device.
Coordinates: 27°55′18″S 23°38′30″E / 27.92167°S 23.64167°E
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