Cave-diving is underwater diving in water-filled caves. It may be done as an extreme sport, a way of exploring flooded caves for scientific investigation, or for the search for and recovery of divers or, as in the 2018 Thai cave rescue, other cave users. The equipment used varies depending on the circumstances, and ranges from breath hold to surface supplied, but almost all cave-diving is done using scuba equipment, often in specialised configurations with redundancies such as sidemount or backmounted twinset. Recreational cave-diving is generally considered to be a type of technical diving due to the lack of a free surface during large parts of the dive, and often involves planned decompression stops. A distinction is made by recreational diver training agencies between cave-diving and cavern-diving, where cavern diving is deemed to be diving in those parts of a cave where the exit to open water can be seen by natural light. An arbitrary distance limit to the open water surface may also be specified.
Diving activities are the things people do while diving underwater. People may dive for various reasons, both personal and professional. While a newly qualified recreational diver may dive purely for the experience of diving, most divers have some additional reason for being underwater. Recreational diving is purely for enjoyment and has several specialisations and technical disciplines to provide more scope for varied activities for which specialist training can be offered, such as cave diving, wreck diving, ice diving and deep diving. Several underwater sports are available for exercise and competition.
Mount Gambier is the second most populated city in South Australia, with an estimated urban population of 33,233 as of 2021. The city is located on the slopes of Mount Gambier, a volcano in the south east of the state, about 450 kilometres (280 mi) south-east of the capital Adelaide and just 17 kilometres (11 mi) from the Victorian border. The traditional owners of the area are the Bungandidj people. Mount Gambier is the most important settlement in the Limestone Coast region and the seat of government for both the City of Mount Gambier and the District Council of Grant.
A cenote is a natural pit, or sinkhole, resulting from the collapse of limestone bedrock that exposes groundwater. The term originated on the Yucatán Peninsula of Mexico, where cenotes were commonly used for water supplies by the ancient Maya, and occasionally for sacrificial offerings. The term derives from a word used by the lowland Yucatec Maya—tsʼonoʼot—to refer to any location with accessible groundwater.
Vortex Spring is a commercially operated recreation, camping and dive park located near Ponce de Leon, Florida. It is the largest diving facility in the state of Florida.
The District Council of Grant is a local government area located in the Limestone Coast region of South Australia, and is the southernmost council in the state.
Paul Hosie is an Australian cave diver.
Piccaninnie Ponds Conservation Park, formerly the Piccaninnie Ponds National Park, is a protected area of 862 hectares located in southeastern South Australia near Mount Gambier.
Ewens Ponds is a series of three water-filled limestone sinkholes in the Australian state of South Australia located in the gazetted locality of Eight Mile Creek, on the watercourse of Eight Mile Creek about 25 kilometres south of Mount Gambier and 8.4 kilometres east of Port Macdonnell. The ponds are popular with recreational divers due to underwater visibility of up to 80 metres. It has a large fish population including the endangered golden pygmy perch. Ewens Ponds has been part of the Ewens Ponds Conservation Park since 1976.
The Blue Hole of Santa Rosa, or simply the Blue Hole, is a circular, bell-shaped pool or small lake located along Route 66 east of Santa Rosa, New Mexico that is a tourist attraction and swimming venue, and one of the most popular dive destinations in the US for scuba diving and training. The Blue Hole is an artesian well and cenote that was once used as a fish hatchery.
Diving equipment is equipment used by underwater divers to make diving activities possible, easier, safer and/or more comfortable. This may be equipment primarily intended for this purpose, or equipment intended for other purposes which is found to be suitable for diving use.
The Cave Divers Association of Australia (CDAA) is a cave diving organisation which was formed in September 1973 to represent the interests of recreational scuba divers who dive in water‐filled caves and sinkholes principally in the Lower South East of South Australia (SA) and secondly in other parts of Australia. Its formation occurred after a series of diving fatalities in waterfilled caves and sinkholes in the Mount Gambier region between 1969 and 1973 and in parallel to a South Australian Government inquiry into these deaths. The CDAA's major achievement has been the dramatic reduction of fatalities via the introduction of a site rating scheme and an associated testing system which was brought in during the mid-1970s. While its major area of operation is in the Limestone Coast region of SA, it administers and supports cave diving activity in other parts of Australia including the Nullarbor Plain and Wellington, New South Wales.
Little Blue Lake is a water-filled sinkhole (“cenote”) in the Australian state of South Australia located in the state's south-east in the locality of Mount Schank about 20 kilometres (12 mi) south of the municipal seat of Mount Gambier. It is notable locally as a swimming hole and nationally as a cave diving site. It is managed by the District Council of Grant and has been developed as a recreational and tourism venue.
Fossil Cave (5L81), formerly known as The Green Waterhole, is a cave in the Limestone Coast region of south-eastern South Australia. It is located in the gazetted locality of Tantanoola about 22 kilometres north-west of the city of Mount Gambier, only a few metres from the Princes Highway between Mount Gambier and Millicent. It is popular with cave divers and is notable for being both a unique paleontological site and the "type locality" for very rare crustaceans which to date have been found only in caves and Blue Lake in the Mount Gambier region.
Cave Garden / Thugi, formerly known as the Cave Gardens, is a garden located in the centre of Mount Gambier, South Australia, that contains a 30 m (98 ft) deep cave. The cave was initially used as a water source for the town.
Engelbrecht Cave is a cave system in the Australian state of South Australia consisting of a sinkhole with two major passages located under the Mount Gambier urban area. It is owned by the local government area of City of Mount Gambier and has been developed as a tourism venue. Its dry extent is notable as a show cave while its water-filled extent is notable as two separate cave diving sites.
The following outline is provided as an overview of and topical guide to underwater diving:
The 1973 Mount Gambier cave diving accident was a scuba diving incident on 28 May 1973 at a flooded sinkhole known as "The Shaft" near Mount Gambier in South Australia. The incident claimed the lives of four recreational scuba divers: siblings Stephen and Christine M. Millott, Gordon G. Roberts, and John H. Bockerman. The four divers explored beyond their own planned limits, without the use of a guideline, and subsequently became lost, eventually exhausting their breathing air and drowning. As of May 2015, they are the only known fatalities at the site. Four other divers from the same group survived.
Cave diving is underwater diving in water-filled caves. The equipment used varies depending on the circumstances, and ranges from breath hold to surface supplied, but almost all cave diving is done using scuba equipment, often in specialised configurations with redundancies such as sidemount or backmounted twinset. Recreational cave diving is generally considered to be a type of technical diving due to the lack of a free surface during large parts of the dive, and often involves planned decompression stops. A distinction is made by recreational diver training agencies between cave diving and cavern diving, where cavern diving is deemed to be diving in those parts of a cave where the exit to open water can be seen by natural light. An arbitrary distance limit to the open water surface may also be specified. Despite the risks, water-filled caves attract scuba divers, cavers, and speleologists due to their often unexplored nature, and present divers with a technical diving challenge.
