SS Thistlegorm, Egypt
When a German bomb tore through her port side in 1941, the SS Thistlegorm sank to a watery grave in the Egyptian Red Sea—and into the annals of diving history. Discovered by nautical legend Jacques Cousteau in 1956, the Thistlegorm is a spectacular sunken museum of motorbikes, cargo trucks, tanks, artillery shells and other World War II relics. Few wrecks can match her for physical grandeur, or for tourist traffic. The Thistlegorm is such a busy dive that, in 2007, Egyptian officials were forced to restrict access as they worked to repair damage done by reckless divers. Still, she stands hull and mast above most of the world's wrecks.
SS Yongala, Australia
The Great Barrier Reef might be Australia's top natural attraction, but the historic wreck of the SS Yongala is one of the world's underwater wonders. Rocked by a cyclone whirling off the coast of Cape Bowling Green in 1911, the Yongala sank with more than 120 passengers onboard. It was nearly half a century before she was discovered, and by then the area's rich marine life had adapted to create a spectacular artificial reef. Because of the biodiversity in the region, the Yongala is inhabited by an astonishing array of sea creatures. Barracudas, tiger sharks, sea turtles and eagle rays are abundant; so are the massive Queensland groupers that locals affectionately refer to as VW's.
Built as a freighter in 1912, the Umbria was transporting more than 300,000 bombs to Italian troops when she was stopped by British forces in 1940, just months before the outbreak of World War II. Anxious to see her fall in the hands of the enemy, the Italians sunk the Umbria and her impressive cargo to the bottom of the Red Sea. The wreck is superbly intact, small enough to explore on one dive but large enough to offer plenty of good penetration—from the holds to the engine room to the ship's bakery. Bombs litter the wreck; this being an Italian ship, so do wine bottles. Because it sits off the coast of Sudan, the Umbria sees just a fraction of the traffic of its northern neighbors in Egypt, and on a good day you'll have the site to yourself.
Rainbow Warrior, New Zealand
Every wreck has a story behind it, but few are as loaded with intrigue as the sinking of the Rainbow Warrior. In July 1985, Greenpeace demonstrators had been preparing the ship to sail to the Moruroa Atoll to protest French nuclear testing. Late one night, two explosions rocked the ship as she was docked in Auckland harbor. The French Secret Service was implicated in the bombing that left one dead. Though the Rainbow Warrior was briefly re-floated, extensive damage left her beyond repair, and she was re-sunk in December 1987 off the coast of Motutapere Island. Blue and pink anemones cover the hull with spectacular bursts of color. Dolphins and manta rays drift about the bow rails, and sharks have been known to circle the site—perhaps looking for a nibble.
SS President Coolidge, Vanuatu
When she was christened by the widow of her namesake in 1931, the President Coolidge was as opulent as any pleasure ship plying the world's waters, with an elegant smoking lounge, a shopping arcade, even its own stock exchange. A decade later the Coolidge was converted to an Army transport ship to help with the war effort; she was bringing reinforcements to American troops in the South Pacific when she struck a mine and sank off the coast of Vanuatu. Penetration is superb, and skilled divers can explore the engine room and dining room, or drift along the promenade deck. The largest and most accessible wreck of the Second World War, the Coolidge is in a class of her own.
Fujikawa Maru, Micronesia
While Micronesia isn't on most tourist hot lists, this Pacific archipelago might be the top dive spot on the planet. Truk Lagoon, in particular, draws divers to its legendary graveyard of sunken World War II ships. The Fujikawa is arguably the most famous of Truk's wrecks; sitting almost even keel at the bottom of the lagoon, she's remarkably well-preserved. Built as a passenger and cargo ship by the Mitsubishi Company, the Fujikawa was commandeered by the Japanese navy in 1940, and spent much of the war ferrying aircraft before a torpedo tore through her hull in 1944. Divers are greeted by a spectacular six-inch gun mounted to her bow, but it's the hold full of Zero fighter planes that's this ship's show-stopper. Wings and nose cones litter the wreck; there's even an intact cockpit—an eerie sight far beneath the surface.
USS Saratoga, Marshall Islands
A casualty of American nuclear testing in the Bikini Atoll shortly after the Second World War, the spectacular Saratoga is a behemoth—close to 880-feet-long, with much of the ship well-preserved and ready for exploration. Intact planes sit on the hanger deck—and litter the seabed around it—while racks of torpedoes are stored below. Divers can penetrate deep into the galleys and the captain's quarters, where shaving kits, books and other personal belongings remain. Passing through the ship's workshops, you can still find hammers and screwdrivers lying about; there's even a fully stocked dentistry, complete with chair and drills!
It was during her maiden voyage that the Zenobia—a ferry built to cruise the waters of the Mediterranean—was found to have a faulty computer system; despite extensive work, the ship couldn't be salvaged. Sunk to the bottom of the sea off the coast of Cyprus, she's a marvelously intact wreck, with more than 100 articulated lorries—and much of their cargo—still preserved onboard. Divers can drift through the ghostly passageways and inspect the canteen; a lorry full of eggs makes for an oddly arresting sight. Barracuda and grouper busy about the ship, but it's the abundant cargo that gives the Zenobia her well-deserved fame.
IJN Akitsushima, Philippines
Coron Island is celebrated for its stunning collection of World War II relics, but it's the Akitsushima—perhaps the only warship among the island's many wrecks—that manages to steal the show. Fortunate to survive aerial bombardments by American planes over Truk Lagoon, the Akitsushima made it as far as the Philippines before fresh bombing sunk her to the bottom of Coron Bay. Penetration inside the ship is spectacular, and divers can wend their way through narrow corridors or explore the remains of the engine room. Anti-aircraft guns and shells are abundant, while a massive crane, used to pluck seaplanes from the water, lies in eerie repose on the ocean floor.
RMS Rhone, British Virgin Islands
Hailed as the fastest ship of her time, the RMS Rhone was a marvel of 19th-century nautical engineering. Used to transport mail and passengers between England and the British Virgin Islands, the massive, steel-bellied steamship was rocked by a hurricane off the coast of Salt Island in 1867. She was dashed on the rocks and sunk to the seafloor, where she remains the finest of the Caribbean's wrecks. The ship's bow is largely intact and a giant, 15-foot propeller looms beneath the stern. Coral clings to the hull, and colorful schools of fish dart around the wreck. Keep your eyes peeled for the octopus and giant green moray that call the Rhone home—they're considered good luck for any divers fortunate enough to spot them.