The Heart of Voh, the Cœur de Voh, is a clearing of about four hectares in the mangroves of the northwest coast of Grande Terre, the main island of New Caledonia, shaped so nearly into a perfect heart that it has become the symbol of the island, and it can be read only from the ridge above it or from the air. The heart is a bare patch in the mangrove where the salt is too strong for the trees to grow, its outline drawn by the channels that drain the swamp, and it is the accident of a photograph: Yann Arthus-Bertrand shot it from a helicopter in 1990 for the cover of his book The Earth from Above, and the picture went around the world. On the ground there is nothing to see; the mangrove is a flat grey-green maze at the edge of the lagoon. The way to see the heart is to climb Mont Katépahie, the ridge behind the town of Voh, on a path of 7.7 kilometres there and back with 340 metres of climb and almost no shade, and from the crest the heart appears below, greener and blurrier than the famous photograph because the mangrove is slowly closing in on it.
The other way is the air. Small planes and ultralights lift off from the local airstrip and bank low over the clearing, the one angle where the heart reads as crisply as it does on the book cover, and the flight goes on over the lagoon, the pale water held in by a barrier reef that all but rings the whole island, the largest lagoon in the world. Voh itself is a small town of the Kanak north, far from the capital at Nouméa, with the nickel mines in the hills behind it and the mangrove in front. The heart is quietly closing as the trees creep in, and one day it may be gone. The Heart of Voh is a shape the swamp made by chance, and the whole island has adopted it.