Truk Lagoon holds more shipwrecks than anywhere else on Earth, and all of them went down in the same two days. The atoll, in Chuuk in the western Pacific, is a natural harbour about eighty kilometres across inside a reef, and it was the Japanese navy's main base in the central Pacific. In February 1944 American carrier aircraft caught the shipping at anchor. Warned by reconnaissance flights, the battleships and carriers had already pulled out for Palau, so what the strikes found were tankers, freighters and supply ships. More than two hundred thousand tons went to the bottom in forty-eight hours, more Japanese tonnage than any other action of the war. It is all still where it fell, between about ten metres down and sixty, and nothing has been raised.
The sea has been working on it since. Warm, sheltered water with no current let coral settle on steel quickly, so the hulls are now among the richest reefs in the Pacific. The tanker Shinkoku Maru carries coral gardens off its masts and railings, with anemones, clownfish and turtles in them, and reef sharks working the superstructure above you. The Fujikawa Maru sits upright in about thirty-four metres, its deck gun and upper works fused under decades of soft coral, and reef fish patrol the passageways as you swim them. Some of the ships rise close enough to the surface that you can look down on masts and gun mounts furred over with coral, with sunlight still reaching them. Below decks nothing has moved. Gas masks, rifles and bottles are lying where they settled in 1944, and a torch beam is how you see them. For twenty-five years almost nobody came; Jacques Cousteau filmed the fleet in 1969, and divers have come ever since. Nothing is lifted and nothing is moved. The ships are war graves, and hundreds of the men who were aboard them never came off.