Bikini Atoll is a ring of islands around a lagoon in the Marshall Islands that absorbed twenty-three nuclear tests between 1946 and 1958. The people who lived on it were moved off in 1946, for what they were told would be a short time, and have not come back. The largest was Castle Bravo, in 1954. It was designed for six megatons and gave fifteen, the worst radiological accident in American history. The fallout drifted east over neighbouring atolls and dusted a Japanese fishing boat, and the word entered everyday language that spring. None of that is what the lagoon looks like now. The water is warm, clear and completely ordinary to swim in: its radiation washed out into the Pacific decades ago. About seventy per cent of the coral species recorded before the tests are back, and large colonies now grow inside the Bravo crater itself. Scientists sample them to learn how their cells shrug off radiation.
The reason divers come is on the floor. The fleet anchored here as targets in 1946 is still down there, most of it near fifty metres. The carrier USS Saratoga stands upright with her flight deck at twenty-seven metres and aircraft parked in the hangar below. She is 270 metres long, so no single dive gives you all of her. Getting there takes a liveaboard a day and a half out of Kwajalein, and only in the months when the trades drop, so a few dozen people a year see any of this. Ashore, the concrete bunkers built to shelter cameras and instruments still stand among the palms, walls a metre thick and floors open to the sky, and you can walk into them. They are the only structures that survived what they were built to watch. The palms behind them were replanted over the emptied village, and the fruit above your head is the one thing here nobody may touch, because caesium travels up out of the soil into the coconuts. You can swim, dive and walk here all day. It is eating that cannot be done, and that is what keeps the families away.