The small island of Maré in fact is an uprised coral atoll. The movement of tectonic plates rose it above the sea level, exposing the Miocene limestone layers to the tropical climate and the incredible force of hurricanes.

Rain and groundwater has created countless sinkholes and caves on the surface of the island. In satellite images are seen some 50 sinkholes, but the dense bush and forest hides a lot more.

In earlier times sea level was lower than now – 15,000 years ago it was by 100 m lower. Now the lower part of these sinkholes is submerged.

There is fresh rainwater in these sinkholes – although the deepest parts in some of these unusual lakes are slightly saline. Small (and not so small) creatures live in these lakes and most likely many of these small animals – crustaceans and others – are endemic, found only in these caves – although they still are waiting for their discovery.

Many of these sinkholes (just like the similar cenotes in Mexico) are considered to be sacred and permission from local people should be asked before visiting them.

Trou de Bone is one of the best known sinkholes in Maré Island. The entrance part is some 30 m wide. The sinkhole is approximately 40 m deep, with a lake in it. The roots of large banyan trees reach the water, creating a feeling of a lush tropical garden. The sinkhole has a fine echo effect.

Trou de Bone on the map

Location, GPS coordinates:	21.4638 S 167.9336 E
Categories:	Sinkholes, Lakes and streams
Values:	Geology, Visual
Rating:
Where is located?	Australia and Oceania, Melanesia, New Caledonia, Loyalty Islands, central – northern part of Maré Island
Depth:	40 m

Landmarks of New Caledonia

New Caledonia does not belong to mainstream tourist destinations but this Pacific island country is a true gem with many unusual landmarks. Most interesting landmarks are unique ecosystems, various karst formations and exciting fossil finds.

Sinkholes

Category includes outstanding sinkholes – large natural depressions or holes, which for most part represent collapsed caves.

Recommended books

Lonely Planet Vanuatu & New Caledonia

Lonely Planet Vanuatu & New Caledonia is your passport to the most relevant, up-to-date advice on what to see and skip, and what hidden discoveries await you. Stare into the volcanic cauldron of Vanuatu’s Mt Yasur; eat snails by turquoise coves on New Caledonia’s Ile des Pins; or discover traditional tribal culture.

Cannibal island;: The turbulent story of New Caledonia’s cannibal coasts