Maré Island or Nengone is the second-largest of the Loyalty Islands, in the archipelago of New Caledonia, an overseas territory of France in the Pacific Ocean. The island is part of the commune of Mare, in the Loyalty Islands Province of New Caledonia. The island is 42 km long and 16 to 33 km wide. It lies northeast of Grande Terre, New Caledonia's mainland. Like its neighbor to the north Lifou, Mare is a raised coral atoll, a former atoll that has been lifted about 120 meters. The interior of the island is the former lagoon, surrounded by a rim of higher land that was the ring of reef islets. Its fossil coral rock is honeycombed with caves, pools, and pits of all sizes, whose sharp edges make for difficult walking. Because of the lifting, the current shoreline is relatively recent and supports only short sections of nearshore fringing reef, unlike the extensive barrier reef found on the main island of New Caledonia, Grande Terre. The narrow beaches of Mare are often backed by cliffs.