Kilsby sinkhole

The sinkhole is located on private property owned by the Kilsby family since the late 19th century.[3] Due to insurance and liability concerns, access to the site is highly controlled.[4] Some commercial dive companies teach diving at the site, and limited independent recreational diving and snorkelling is allowed.[5]

In the late 1960s cave and sinkhole diving gained popularity in the area, leading to frequent dives of inexperienced divers at the Kilsby sinkhole.[6]^: 14 On April 6, 1969, two such inexperienced divers died at the Kilsby sinkhole.[6]^: 14[4] Later that year, and until at least 1983, the Australian Department of Defence took on an exclusive lease on the sinkhole and did not allow public access or recreational diving.[6] In the 1970s the site was used to test the Barra Sonobuoy, a classified submarine detection buoy.[7][8][9] The sinkhole has been consistently used to train police divers of the South Australian Police since the early 1980s.[5][4]

Since 1969 six divers have died diving the sinkhole. In 1969 three divers died while diving there.[4] In 2010 a diver died when he became entangled in a cable 37 metres below the water's surface.[10][4] Two others died diving the sinkhole the same year.[11][4]

• Official site