Cook Islands
Rarotonga, the main and most populous island of the Cook Islands, is ringed by a shallow fringing reef and is the country's principal scuba diving base.
Rarotonga is surrounded by a fringing coral reef ranging from about 30 to 900 metres wide, with an outer reef slope dropping steeply into deep water. Two dedicated marine reserves, the Aroa Lagoon Marine Reserve and the Tikioki Marine Reserve, protect sections of the reef and lagoon. Multiple licensed dive operators run reef, wreck and small-cave dives.