Cave diving is a type of technical diving in which specialized equipment is used to enable the exploration of caves which are at least partially filled with water. In the United Kingdom it is an extension of the more common sport of caving, and in the United States an extension of the more common sport of SCUBA diving. Compared to caving and SCUBA diving, there are relatively few practitioners of cave diving. This is due in part to the specialized equipment (such as rebreathers, diver propulsion vehicles and dry suits) and skill sets required, and in part because of the high potential risks, including decompression sickness and drowning. Despite these risks, water-filled caves attract SCUBA divers, cavers, and speleologists due to their often unexplored nature, and present divers with a technical diving challenge. Underwater caves have a wide range of physical features, and can contain fauna not found elsewhere.
Contributions by RexxS, Pbsouthwood, and Cowdy001.