Hundreds of sculptural coral species and fish unique to these waters are flaunted a swim from Fiji’s offshore islands and reefs – no wonder this beach-blessed South Pacific archipelago is one of the world’s most dazzling dive destinations. The best time to go is April through December: the warmer the water, the better the visibility.
 

Warm, clear Indian Ocean waters teeming with aquatic life rainbow-coloured fish, soft corals and fascinating crustaceans – each of the Maldives’ islands is a dreamy desert-island idyll. The archetypal honeymoon destination, these far-flung palm-tree hideaways tick all the tropical-island boxes, offering balmy seclusion above water, and a spectacular undersea landscape below.

This rugged Aegean beauty, the southernmost of the Cyclades, is famed for its sunsets, wine and turquoise sea. What makes Santorini especially compelling for scuba diving is its caldera: this vast volcanic bay promises magnificent underwater scenery. Navigate lava flows, reefs, and wrecks in clear waters not just by day – night dives here too can be entertaining.
 

Part of the Coral Triangle, this archipelago of over 7,000 islands is abundant in eye-poppingly interesting indigenous species. Cebu in the Visayas region and its surrounding islands is best viewed by the sea – it takes around two hours to circumnavigate Mactan by boat. Diving is spectacular off Pamalican Island, a 70-minute flight from the Philippines capital, Manila, where seven kilometres of kaleidoscopic coral reef encircles the land.
 

Luminescent coral and rainbow-coloured fish usually only visible in scenes from The Blue Planet are just some of the entertainment waiting waiting in these Indian Ocean waters. And with only a relatively small smattering of land in the midst of such a vast sea, unsurprisingly this is one of the best places on earth for watersports. Thrills await on terra firme too with some of the world’s rarest plant and animal species visible.
 

Sure this Indonesian island impresses with its sun, sand and surf shenanigans but it’s the diving here that really impresses. All the action is easily accessible from shore, and our tip-off is to take a great underwater camera. These waters are ripe for wide-angle snaps with some seriously impressive macro subjects to capture. For the best experience, head to sites in the south from May to September.
 

This cluster of coral-fringed Caribbean isles float in a sea that shifts through shades of turquoise neon. It’s not just spellbinding below sea level… dabblers should look out for the donkeys roaming the salt ponds and flamingos that flock to T&C’s shallow waters. Oh, and pack the book Water and Light: A Diver’s Journey to a Coral Reef, Stephen Harrigan’s account of the his exploration of this disappearing Caribbean waterworld.

Whether you scour sky, scrub or sea, Australia’s answer to the Galapagos, KI will wow you with its wildlife. One of the most special creatures to spot among the seaweed? A sea dragon. When your head is above water, look out for southern right whales, dolphins, fairy penguins, Australian sea lions and New Zealand fur seals.