The Best Dive Sites

Port Douglas (QLD): Among the fabulous dive sites off Port Douglas, north of Cairns, are Split-Bommie, with its delicate fan corals and schools of fusiliers; Barracuda Pass, with its coral gardens and giant clams; and the swim-through coral spires of the Cathedrals. Snorkelers can glide over the coral and reef fish life of Agincourt Reef.

Lizard Island (QLD): Snorkel over 150-year-old giant clams -- as well as gorgeous underwater coral -- in the Clam Garden, off this exclusive resort island northeast of Cairns. Nearby is the famous Cod Hole, where divers can hand-feed giant potato cod.

Cairns (QLD): Moore, Norman, Hardy, Saxon, and Arlington reefs and Michaelmas and Upolu cays -- all about 90 minutes off Cairns -- offer great snorkeling and endless dive sites. Explore on a day trip from Cairns or join a live-aboard adventure.

Coral Sea (QLD): In this sea east of the Great Barrier Reef off north Queensland, you'll see sharks feeding at Predator's Playground; 1,000m (3,280 ft.) drop-offs in the Abyss; reefs covering hundreds of square miles; and tropical species not found on the Great Barrier Reef. This is not a day-trip destination; many dive operators run multiday trips on live-aboard vessels. Visibility is excellent -- up to 100m (328 ft.).

Yongala wreck (QLD): Sunk by a cyclone in 1911, the 120m (394-ft.) SS Yongala lies in the Coral Sea off Townsville. Schools of trevally, kingfish, barracuda, and batfish surround the wreckage; giant Queensland grouper live under the bow, lionfish hide under the stern, turtles graze on the hull, and hard and soft corals make their home on it. It's too far for a day trip; live-aboard trips run from Townsville and Cairns.

The Whitsunday Islands (QLD): As well as Blue Pearl Bay, these 74 breathtaking islands offer countless dive sites both among the islands and on the Outer Great Barrier Reef, 90 minutes ctix. Bait Reef on the Outer Reef is popular for its drop-offs. Snorkelers can explore not just the Outer Reef, but also patch reefs among the islands and rarely visited fringing reefs around many islands.

Heron Island (QLD): Easily the number-one snorkel and dive site in Australia. If you stayed in the water for a week, you couldn't snorkel all the acres of coral stretching from shore. Take your pick of 22 dive sites: the Coral Cascades, with football trout and anemones; the Blue Pools, favored by octopus, turtles, and sharks; Heron Bommie, with its rays, eels, and Spanish dancers; and more. Absolute magic.

Lady Elliot Island (QLD): Gorgeous coral lagoons, perfect for snorkeling, line this coral cay island off the town of Bundaberg. Boats take you farther out to snorkel above manta rays, plate coral, and big fish. Divers can swim through the blow hole, 16m (52 ft.) down, and see Gorgonian fans, soft and hard corals, sharks, barracudas, and reef fish.

Rottnest Island (WA): Just 19km (12 miles) off Perth, this former prison island has excellent snorkeling and more than 100 dive sites. Wrecks, limestone overhangs, and myriad fish will keep divers entertained. There are no cars, so snorkelers should rent a bike and snorkel gear, buy a visitor-center map of suggested snorkel trails, and head off to find their own private coral garden. The sunken grotto of Fishhook Bay is great for fish life.

Ningaloo Reef (WA): A well-kept secret is how we'd describe Australia's second great barrier reef, stretching 260km (161 miles) along the Northwest Cape halfway up Western Australia. Coral starts right on shore, not 90 minutes out to sea as at the Great Barrier Reef. You can snorkel or dive with manta rays, and dive to see sharks, angelfish, turtles, eels, grouper, potato cod, and much more. Snorkel with whale sharks up to 18m (59 ft.) long from March to early June.

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