Snorkeling and Diving

Eye to Eye Marine Encounters. On these all-inclusive, dive/snorkel live-aboard trips, you visit world-renowned northern Great Barrier Reef and Coral Sea sites, including 2,000-foot drop-offs and pristine coral gardens, top shark-spotting sites, and turtle-nesting grounds. John Rumney, who pioneered swim-with-whales in Queensland, brings 30-plus years of experience on the Reef and extensive ecological knowledge and nautical expertise to the expeditions, working with highly skilled divers, scientists, and skippers to ensure each trip is as exciting as it is eco-friendly. 10 Captain Cook Hwy., Port Douglas, Queensland, 4877. 07/4098–5417; 0417/726–622; www.marineencounters.com.au.

Poseidon. Excellent pre-dive briefings from a marine naturalist, high safety standards, and a wide choice of dive and snorkeling sites make this advanced eco-certified operator a smart choice. Poseidon runs guided snorkeling and PADI-style diving trips to sites at three separate reef sites at the Agincourt Ribbon Reef on a small, usually uncrowded boat. A day's cruise to three Agincourt sites includes a marine biologist–guided snorkel tour, lycra suits, masks, snorkels, fins, and flotation devices; wet suits for snorkelers can be rented at A$7 per day. For certified divers, a full day in the water includes dive gear. Morning and afternoon tea and a buffet lunch are provided for all guests. Port Douglas transfers are free; from Cairns or the Northern Beaches, it's A$28. Reef Marina, Wharf St., off Inlet Dr., Port Douglas, Queensland, 4877. 07/4087–2100; www.poseidon-cruises.com.au. From A$232 (cruise and snorkeling), from A$278 (with diving), A$6.50 reef/admin tax. Daily 8:30–4:30.

Quicksilver Cruises. Quicksilver's fast, modern catamarans speed you from Port Douglas's marina to a large commercial activity platform on the outer Barrier Reef. There, you can dive and snorkel with the reef residents, and make leisurely sail-and-snorkel trips to Low Isle coral cays. Options at Agincourt Reef include marine-biologist-guided snorkeling tours (A$60–A$78), introductory or certified scuba dives (extra A$118–A$166), 10-minute scenic heli-tours (A$175), and "Ocean Walker" sea-bed explorations (A$166). There's also a semi-submersible underwater observatory, included in the A$238 rate. A quieter sailing trip to a Low Isles coral cay, closer to shore (A$188), includes a biologist-guided glass-bottom-boat trip and snorkeling. Everyone pays a A$6.50 reef tax. The trip includes a varied lunch buffet and dive/snorkel gear. Transfers are available from Port Douglas accommodations and farther afield (A$12–A$28). The Reef Marina, Wharf St., off Inlet Dr., Port Douglas, Queensland, 4877. 07/4087–2100; www.quicksilver-cruises.com. From A$118.

The Silver Series: Silversonic. High-end, high-speed catamaran Silversonic whisks visitors to three pristine dive-snorkel sites on Agincourt Reef, known for its high-visibility waters. There, you can spend five hours amid spectacular corals on the edge of the Coral Sea trench, with turtles, rays, tropical fish, large pelagic species, and, in season, the odd Minke whale. Full-day outer reef cruises run daily, weather permitting; the A$232 tariff includes a "tropical smorgasbord" lunch, morning and afternoon tea, Wi-Fi, snorkeling, and gear; all scuba dives are guided at no extra cost, and everyone pays a A$6.50 reef tax. Coach transfers from local accommodations are included in the cruise fare; transfers to and from Palm Cove, the Northern Beaches, and Cairns are available for a surcharge. The Reef Marina, 1 Wharf St., off Inlet Dve., Port Douglas, Queensland, 4877. 07/4087–2100; www.silverseries.com.au. From A$232, with EMC charge of A$6.50.

Wavedancer. The palm-fringed Low Isles have a rich history, but the main attractions lie underwater, in the fringing coral gardens, which shelter bright parrotfish and "Nemos," giant clams and green turtles. The sleek, speedy sailing cat Wavedancer is one of the best ways to get there. When you tire of snorkeling, you can join a glass-bottomed boat tour, a marine biologist–guided shore stroll or heritage walk (on which you'll visit the island's lighthouse), or relax and soak up some rays. Quicksilver's day cruise on 98-foot sailing catamaran Wavedancer whisks you from Port Douglas to the Low Isles in less than an hour, allowing plenty of time for snorkeling, sunbathing and strolling; the rate includes all snorkeling gear, reef presentations, supervised snorkeling (including guided expeditions), glass-bottom boat tours, a tropical buffet lunch, morning and afternoon tea. Coach transfers from Port Douglas, Cairns, and the Northern Beaches are available for a fee. Bring a towel, hat, sunscreen, swimsuit, and shirt (to avoid sunburn); cash to buy bar drinks and souvenirs; and a credit card for underwater camera hire. The Reef Marina, 1 Wharf St., off Inlet Dve., Port Douglas, Queensland, 4877. 07/4087–2100; www.quicksilvergroup.com.au. From A$188 cruise, with A$6.50 EMC/admin charge.