Likuan is a long reef wall that in places (Likuan 1) can be subject to strong currents. But divers love it for the variety of small creatures combined with a dramatic drop-off that offers the prospect of sharks and eagle rays in the blue nearby. Indonesia is part of the coral triangle, the epicentre of marine biodiversity.
Few divers will be able to go under water here and claim they haven't seen something new. Many creatures live here, including pygmy seahorses, which come in a subtle range of colours but are no bigger than the end of your little finger.
Diver level: Moderate experience.
Season: Year round.
Lea Lea's Lookout, Bloody Bay, Little Cayman
Best for: Underwater scenery
Little Cayman is a sandy dot of perfection southwest of Cuba. Home to the Bloody Bay Marine Park, it has arguably the healthiest coral reefs left in the entire Caribbean. Lea Lea's Lookout is typical of the wall-diving here, a shallow (5m/16ft) reef top cut through with tunnels and sand chutes that lead downwards and out on to the sheer vertical reef wall. Cayman has the best underwater visibility in the world, and the abyss plunges into an infinity of dizzying blue. Seahorses have been spotted here, as have inquisitive Caribbean reef sharks, hawksbill turtles and bolshie Nassau groupers here, and some of the biggest giant sponges in the world.
Diver level:
Beginners and beyond with good buoyancy control
Season:
Year round.
Niue
Best for: Clear water
The waters around Niue's coastline are famously clear with the limestone of the island acting as a giant filtration system. There's abundant fish life and the distinctive banded sea snakes are alarmingly friendly, swimming over and around divers as they chase the small fish on which they prey.
Diver level: All levels.
Season: Year round.
The Tiputa Pass, Rangiroa, French Polynesia
Best for: Diving with sharks
Rangiroa means "endless sky" and is one of the most romantic parts of Polynesia.
Underwater, there is a sense of rawvitality, and at Tiputa youwill dive repeatedly with large schools of grey reef sharks, turtles, manta rays and, on one occasion, all of the above within view while dolphins passed overhead.
The pass is one of just two entrances into the vast interior lagoon and dives have tobe conducted on an incoming tide to avoid divers being swept out into the Pacific.
Diver level: Experienced.
Season: Any time except December-January. September is best for sharks.
The Poor Knights Islands, off the coast of Tutukaka, near Whangarei
Best for: Underwater colour
Jacques Cousteau named the Poor Knights Islands as one of the top-10dive sites in the world.
Vibrant fish populations dart around swirling forests of kelp and sponges where warm currents from the north meet sharper southern swirls. Keep an eye out for humpbacks and turtles. In winter, divers can see up to 30m. Plankton decreases visibility in warmer months, but the fish life ismore abundant.
Diver level: All levels.
Season: January to June is best.
Challenger Bay, Ribbon Reefs
Best for: Nocturnal
No list of top diving sites would be complete without a mention of Queensland's Great Barrier Reef. The hard-coral gardens of the Ribbon Reefs bring in schools of trevally and surgeon fish and it's particularly stunning at night when the fish populations get really busy.
Diver level:
Experienced.
Season:
Year round.
Wreck of the Giannis D, Abu Nuhas, Egypt
Best for: Wreck diving
The Giannis D cargo ship struck the coral reef en route from Croatia to Saudi Arabia 30 years ago. It's not the world'smost dramatic, nor one of the largest underwater wrecks, but it's very atmospheric and gives even inexperienced divers a taste of the adventure that makes wreck diving appealing.
The topmost parts of the ship are only about 20ft below the surface, with the stern sitting on sand at about 100ft. Thanks to the proximity of the reef and the age of the wreck, there is always a lot of marine life, and the sight of the stern resting on the seabed with the funnel still upright makes for eerie, poignant photographs.
Diver level: All levels.
Season: Year round.
Noonu Atoll, the Maldives
Best for: Colourful marine life
This little gem of a reef is teeming with life: unicorn fish, mantis shrimps, big groupers and numerous varieties of tiny nudibranchs. Large shoals of hunters such as unicorn fish and tuna come hurtling from the open water to pick off the myriad schools of golden anthias that swirl in dense clouds above the healthy hard coral. It's a tiny reef with ledges and overhangs covered inbright cup corals and feathery gorgonians.
Diver level: All levels.
Season: Year round, though November-March may be better for visibility.
BradfordShoals, Kimbe Bay, Papua NewGuinea
Best for: Weirdand wonderful
dives Kimbe Bay is a vast area on the northern edge of New Britain and home to about two thirds of all the fish species in the Indo-Pacific.
With hundreds of reefs, it's hard toname a single site, but Bradford Shoals is as good as any: an oceanic pinnacle surrounded by deep, deep water.
Large schools of barracuda can form into tornado-shaped clouds, silvertip sharks can spiral up from the depths and there will almost inevitably be dolphins off the bow at some time of the day.
Diver level: Experienced.
Season: April-November.
Neptune's Arm, Vamizi Island, Mozambique
Best for: Remote adventure
Several miles offshore, this submarine plateau holds a precious secret. A deep vertical wall, rock gulleys encrusted with coral and a promontory swept by deep-water currents combine to attractmarine life.
When conditions are right therewill be thousands of large snappers, dozens of sharks, plus eagle rays and turtles in this isolated spot. Currents can be fierce, but this is an underwater heaven that only a few lucky diverswill ever see.
Diver level: Moderate to advanced.
Season: Mid-August-December.
