Marovo Lagoon is the largest lagoon on Earth held by a double barrier reef, seven hundred square kilometres of water in the Solomon Islands. Most lagoons are closed off by one line of reef; this one has two. The outer wall takes the force of the open Pacific, and the inner one shelters the calm channels where the canoes move, so there are two worlds inside the same lagoon. There are no roads and no bridges, so everything here moves by water. Villages of sago-palm thatch stand on stilts above it on islets across the reef, reached only by outboard canoe. The islands and the reef around them are owned by the families who live there, so you ask before stepping ashore. The guesthouses are the same thatch on the same stilts, right at the waterline under coconut palms, and you fall asleep to the water working under the floorboards.
Off any beach with a mask, or on the outer walls with a tank, you find terraced coral, giant clams and clouds of reef fish. The passes between the islands pull in the bigger animals — turtles, reef sharks, and dolphins out in the deeper blue. Wood is the other harvest. On a shaded veranda a carver works a bowl or a model canoe out of dense black ebony, then eases slivers of white nautilus shell into the surface until a pattern comes up. That white-on-black is the decoration of the old war canoes, and you buy the carvings from the hand that made them, from tabletop figures to canoes a metre long. Several villages took the carving up partly to fund their resistance to the logging of the rainforest behind them. The whole arrangement only shows from height. A light-plane hop between the grass airstrips lays it out: two pale lines of surf ringing the blue, dark coral heads on the shallows, and the wake of one canoe crossing between them.