Ten snorkelling beaches with reefs right off the sand

Boat trips are all very well, but the purest snorkelling pleasure is walking off a beach and being over coral ninety seconds later. Every beach here has a genuine reef within easy swimming distance of the sand — no schedules, no seasickness, no guide shouting through a megaphone. Two rules travel with you: reef-safe sunscreen only, and never stand on anything that isn't sand. The fish were here first.

A flooded volcanic crater turned nature preserve, Hanauma is effectively a giant natural aquarium: parrotfish, tangs and green turtles cruising coral heads in water rarely deeper than a snorkeller needs. Numbers are capped and reservations required, which has transformed the reef's health. Book the earliest slot, watch the mandatory conservation video with good grace, and you'll have the best of it before the crowds wade in.

On the far side of Australia from the Great Barrier Reef, Ningaloo does something its famous rival can't: coral gardens that begin a wade from the beach. At Turquoise Bay the current drifts you over the reef like a moving walkway — walk up the sand, float down over coral bommies thick with fish, exit before the channel, repeat until pruned. April to July adds whale sharks offshore.

A car-free coral island where the motto — Go Slow — is enforced mainly by hammock. The barrier reef, the largest in the northern hemisphere, sits just offshore: snorkel from the Split's dock area or take the shortest of boat hops to swim with nurse sharks and rays inside Hol Chan reserve. Fry jacks for breakfast, lobster for dinner, and nothing in between but water.

Regularly voted among the world's best beaches, Flamenco is a horseshoe of blinding sand and gin-clear water on a sleepy island east of Puerto Rico proper. Snorkellers head to the rocky ends of the bay for coral, fish and the occasional turtle, or walk over to Tamarindo beach where the seagrass meadows all but guarantee them. The rusting tanks on the sand are relics of the navy years — now murals.

A string of quiet black-sand fishing villages in Bali's dry east, where Mount Agung looms over water full of coral just metres from the outrigger boats. The Japanese shipwreck at Banyuning sits shallow enough to snorkel, and the house reefs of Jemeluk bay are alive again after years of restoration. Life here is early nights, dawn dives and grilled fish — Bali with the volume turned right down.

Mauritius's best snorkelling sits inside a marine park at its south-east corner: a lagoon where visibility runs to thirty metres and the coral — some colonies centuries old — starts within a short swim of the public beach. Weekdays are quietest; glass-bottom boats serve the reluctant. The water is warmest December to April, and the flight home passes tolerably with enough rum in your luggage.

The Mediterranean rarely rewards snorkellers like the coves of Paleokastritsa, where olive-clad cliffs drop into water so clear the boats seem to levitate. There's no tropical coral, but the rocky points teem with bream, octopus and the odd moray, and the swimming-cave circuit by rented pedalo is a highlight of any Greek holiday. The monastery on the headland provides the view; go at opening time.

In the shadow of the Pitons, St Lucia's twin volcanic spires, Anse Chastanet's reef begins a few fin-kicks from the dark golden sand and drops away in tiers of sponge and coral patrolled by trumpetfish and turtles. The marine reserve status shows underwater. It's attached to a famously romantic resort, but the beach — like all in St Lucia — is public. Snorkel the morning, then climb Gros Piton to earn dinner.

Three tufted islets joined by a white sandbar just off Ko Tao, with coral gardens beginning practically at the waterline — Japanese Gardens, the pick of them, is a five-minute swim of parrotfish, angelfish and the occasional blacktip reef shark. Day boats pour in mid-morning, so stay on Ko Tao and catch the first longtail across, then climb the famous viewpoint before the heat builds. February to May brings the calmest, clearest water.

On Egypt's deep-south Red Sea coast, Abu Dabbab's horseshoe bay is famous for two residents: enormous green turtles grazing the seagrass metres from shore, and the occasional dugong — the sea cow that reputedly started the mermaid myth. Coral reefs frame both arms of the bay, visibility is routinely superb, and the water stays warm enough to swim all year. Fly to Marsa Alam, thirty minutes away, and get in early — the turtles breakfast before the crowds do.