Overview

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.[citation needed] The greatest depth attained was by Nuno Gomes in 1996, diving to a depth of 282.6 metres (927 ft). 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) 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.