Bikini Atoll

IslandsRalik Chain,Marshall Islands

Fragile nature — stay on the trail, leave no trace.

The Marshall Islands lagoon that took 23 nuclear tests, its people moved off in 1946 and never returned, a target fleet lying on its floor.

September·Peaking now

May–Oct

The only months anyone reaches Bikini. Liveaboards make the 24-to-30-hour crossing from Kwajalein once the northeast trades fade and the open sea settles; outside this window there is no route in at all.

Year-round The ghost fleet, the recovered reef and the empty beaches are here every month; only the crossing and the diving are seasonal.

Bikini Atoll is a ring of islands around a lagoon in the Ralik chain of the Marshall Islands, in the central Pacific, that took 23 nuclear tests between 1946 and 1958, its people moved off in 1946 for what they were told would be a short time and never returned, and a fleet of target ships lies on the floor of its lagoon, dived by a few dozen people a year in water that is warm, clear and completely ordinary to swim in. The tests began with Operation Crossroads, which sank a fleet of captured and surplus warships anchored in the lagoon as targets, and ended with the hydrogen bombs, among them Castle Bravo in 1954, expected to yield six megatons and delivering fifteen, the largest the United States ever fired, whose fallout poisoned the neighbouring atolls and a Japanese fishing boat; the swimsuit was named four days after the first bomb, by a Paris designer betting on an explosive reaction. The ships are the reason to come: the carrier USS Saratoga stands upright with her flight deck at 27 metres and aircraft still parked in the hangar below, and the Japanese battleship Nagato, flagship of the fleet that attacked Pearl Harbor, lies upside down nearby, most of the wrecks around fifty metres down. The islands are safe to walk and the sea to swim, but the soil is not, and the palms replanted over the evacuated village carry the one thing that must not be eaten, since the coconuts concentrate the caesium in the ground; reinforced bunkers built to shelter cameras and instruments still stand among the palms with walls a metre thick and floors open to the sky. Around seventy percent of the coral species recorded before the tests have returned to the reef, and big colonies now grow inside the Bravo crater itself, two kilometres across. The atoll is reached by liveaboard from Kwajalein for the diving, with visibility past thirty metres and often nearer fifty. Bikini is a lagoon that absorbed the bomb, and the fleet it sank is the visit.

Worth knowing

Good to know

Liveaboards are the only way in — a few expeditions run each year on one boat, and nothing is guaranteed: diving here shut down completely in 2008 and took years to come back.
Kwajalein is a US Army base, and you transit it to reach the boat — clearance letters go through the operator well before you fly, so nothing here can be improvised on arrival.
Everything but the Saratoga's superstructure is decompression diving — most of the fleet lies near 50 metres, and operators expect technical training and full gas redundancy before you board.
Grey reef sharks turn up on almost every dive, patrolling the wrecks and the passes. They are unfed and simply curious; hold your line, let them make the first pass, and they lose interest.
You will not share the water with anyone — the atoll is uninhabited apart from its caretakers, so the wrecks, the reef and the beaches belong to your boat alone.

Things to do

1
Drop onto the flight deck of the USS Saratoga
The carrier stands upright with her deck at 27 metres, wide enough to lose your buddy on, and aircraft still parked in the hangar below. Follow the deck forward and the bow disappears into blue — she is 270 metres long, and no dive gives you all of her at once.
2
Swim in the lagoon that absorbed 23 detonations
The lagoon that absorbed Castle Bravo, the 15-megaton bomb fired here in 1954, is warm, clear and completely ordinary to swim in today. Its radiation washed out into the Pacific decades ago, while the land stayed contaminated. Swimming is unrestricted; it is the beach behind you, and everything growing on it, that is not.
3
Walk beaches that see a few dozen people a year
The palms behind the sand were replanted over an evacuated village, and the fruit above your head is the one thing here you must not touch. The sand runs unmarked in both directions, and the tide wipes your prints before anyone follows them.
4
Step inside the concrete bunkers that watched the bombs
Reinforced bunkers built to shelter cameras and instruments still stand among the palms, walls a metre thick, floors open to the sky. They were made to survive what happened here, and they are the only structures on the atoll that did.