The 3 largest closed lagoons in the world

by spotmydive

The New Caledonia lagoon

The archipelago of New Caledonia, located in the heart of the South Pacific Ocean, was discovered in the 18th century by James Cook, the Scottish navigator. It has the largest lagoon in the world. It is registered since 2008 on the World Heritage list of Unesco. The lagoon of New Caledonia has the second largest barrier in the world after the great barrier reef of Australia, and its marine biodiversity is exceptional. 1,600 km long, it delimits a 24,000-km2 lagoon with an average depth of 25 meters, encompassing Grande Terre, Belep Islands, Isle of Pines and Loyalty Islands, as well as several other smaller islands. It is interspersed with passes that allow the lagoon to communicate with the high seas. True paradises for divers, these lagoons are home to more than 350 species of corals and some 1600 species of fish. The climate is tropical with an average temperature between 15 ° and 32 ° C depending on the season. If you dive in New Caledonia, you will have the choice between the remarkable spots of Cathedral, Sperm Point, Eagle Paradise, the Butterfly Point, Bargibanti, or the Trou aux requins.


Rangiroa, which means vast sky in paumotu, is an atoll of the Tuamotu archipelago in French Polynesia. Its 240 islets are spread over 177 km of ocean, around a deep lagoon, but the inhabitants live on only two of them, Tiputa and Avatoru. With an area of 1,446 km2, it is the second largest atoll in the world.

Diving in Rangiroa, with its powerful passes, hordes of sharks, majestic rays, and schools of trevallies is recognized as one of the best diving destinations in the world. On the TIputa pass you might even dive with wild daulphins that often come to play with divers. The lagoon is simply magical. Three sites are particularly noteworthy, The Blue Lagoon, lagoon inside the lagoon, Reef Island and its fossil coral formations, called “feo”, and the Pink Sands, sandbanks at the southern end of the lagoon. The climate in Rangiroa is tropical.

Two seasons:

  • The rainy season, from November to April.
  • The cool season, from May to October.

Average temperatures range from 28 ° C in July to 31 ° C in April. The temperature of the water varies from 26 ° to 29 °.

The lagoon of Mayotte

Surrounded by a double barrier reef, the Mayotte Lagoon is one of the biggest lagoon in the world. Paradise divers, this huge lagoon with calm waters in the heart of the Indian Ocean, has the particularity of having a double barrier reef. The farthest is 150 km by 100 to 500 meters wide. It is located between 3 and 15 km from the coast, and is cut by twelve passes, one of which, the S-Pass, is very famous among scuba divers. The other barrier, which is only between 200 and 300 meters from the island, is accessible to everyone. It is beautiful around the peninsula of Sazilé, off the beaches of Tsohoa, Mliha, and around the islets of Bandrele, Bambo and Choazi. Mayotte has two marine reserves, the Longogori Fishing Reserve, or the “S-Pass” on the east side of the island, and the Saziley Marine and Land Park in the south. In this paradise, diving in Mayotte is a great experience.

Depending on the season, the temperature of the water varies from 24 ° to 30 ° C, but the water is transparent only during the months of June, September and October, the rest of the time, it is not always clear . The richness of the fauna on the platiers, and along the drop-offs is a delight for divers at a depth of 10 to 20 meters. Masks and snorkels are enough to enjoy the splendor of the seabed.