New Providence Island: Many ships have sunk near Nassau in the past 300 years, and all the dive outfitters here know the most scenic wreck sites. Other attractions are underwater gardens of elkhorn coral and dozens of reefs brimming with underwater life. The most spectacular dive site is the Shark Wall, 16km (10 miles) off the southwest coast of New Providence; it's blessed with incredible, colorful sea life and the healthiest coral offshore. You'll even get to swim with sharks (not as bait, of course).

Grand Bahama Island: The island is ringed with reefs, and dive sites are plentiful, including the Wall, the Caves (the deliberate and well-engineered sinking known as Theo's Wreck), and Treasure Reef. Other popular dive sites include Spit City (yes, that's right), Ben Blue Hole, and the Rose Garden (no one knows how this one got its name). What makes Grand Bahama Island a cut above the others is the presence of a world-class dive operator, UNEXSO (the Underwater Explorer's Society; tel. 888/365-3483 or 242/373-1250).

Andros: Marine life abounds in the barrier reef off the coast of Andros, which is one of the largest in the world and a famous destination for divers. The reef plunges 167km (104 miles) to a narrow drop-off known as the Tongue of the Ocean. You can also explore mysterious blue holes, formed when subterranean caves fill with seawater, causing their ceilings to collapse and exposing clear, deep pools.

Bimini: Although Bimini is most famous for its game fishing, it boasts excellent diving, too. Five kilometers (3 miles) of offshore reefs attract millions of colorful fish. Even snorkelers can see black coral gardens, blue holes, and an odd configuration on the sea floor that is reportedly part of the lost continent of Atlantis (a fun legend, at any rate). Divers can check out the wreck of a motorized yacht, the Sapona (owned by Henry Ford), which sank in shallow waters off the coast in 1929.

Eleuthera: In addition to lovely coral and an array of colorful fish, divers can enjoy some unique experiences here, such as the "Current Cut," an exciting underwater gully that carries you on a swiftly flowing underwater current for 10 minutes. Four wrecked ships also lie nearby, at depths of less than 12m (40 ft.), including a barge that was transporting the engine of a steam locomotive in 1865, reportedly after the American Confederacy sold it to raise cash for its war effort.