Planning a trip to one of these dive hotspots? Here’s what you need to know. Featuring insight from locals, tips for timing seasonal experiences, and the scoop on popular dive sites, as well as some lesser-known dives you’ll want on your radar too.

Indonesia

Under the Radar

In South Sulawesi, Wakatobi’s reefs are the stuff of diving lore. But the Blade dive site remains relatively under the radar. An unusually tall and thin seamount, it stretches some 650 feet long and is crawling with life. “Dropping from an overhead vantage point to either side of this wall-like formation reveals near-vertical surfaces riddled with crevices and caverns, some of which extend all the way through the center of the pinnacle,” says Karen Stearns, of Wakatobi Resort & Pelagian Dive Yacht.

The Classic Dive

There’s a classic dive for every region of Indonesia’s vast archipelago. And travelers who arrive in Bali beeline it for one of the best shore dives on Earth. Offshore from the village of Tulamben, the USAT Liberty wreck rests in 30 to 100 feet of water and is the spot to see everything from pygmy seahorses and juvenile sweetlips to barracuda, schooling jacks, anemonefish and so, so much more.

Dive Report

Recent liveaboard trips from Bali to Flores have come with such regular highlights as mantas, reef sharks, nudibranchs, octopuses and exceptionally healthy coral reef views, says Luigi Russo, of the boutique liveaboard Arenui, which operates trips in Komodo, Raja Ampat and other epic Indo spots.

Plan a Trip

Raja Ampat thrills divers every day of the year. But from October to mid-April, says Joane Esterhuizen, of Meridian Adventure Dive Resort, mark your calendar for the arrival of migrating mantas in the deep waters of the Dampier Strait. “Raja Ampat is one of the very few areas where both reef and oceanic mantas can be found in the same place,” Esterhuizen says. And fans of hammerheads should book a summer liveaboard trip from July onward in the Banda Sea, says Marian Azna Doucet, of the Indonesian Liveaboard Association.

Second-Time Visitor

For another fabulous Bali shore dive just north of Tulamben, set your sights on the Boga cargo ship wreck offshore from Kubu Beach, says Alice Askholm, of AB Wonderdive Bali Resort. Sunk in 2012, the wreck’s penetrations make it a favorite for tec divers at a max depth of around 108 feet. Look for massive barrel sponges, eels and patrolling Napoleon wrasse.

Saba

Under the Radar

With two pinnacles that rise to 100 feet below the water’s surface just south of Saba’s main plateau, Mt. Michel is a less-visited dive site with dramatic seascapes covered in healthy reefs and colorful coral ledges, says Rachel Huber, of liveaboard operator Explorer Ventures. Veteran Saba diver Lynn Costenaro says the island has a fabulous muck dive too (it’s simply called “the muck dive”), in a mooring field where it’s common to spot seahorses, frogfish, pipefish, batfish and flying gurnards.

The Classic Dive

A seamount called Man o’ War Shoals comes within just 15 feet of the water’s surface, and it is Saba’s must-dive site, says Chad Nuttall, of Sea Saba. Two peaks with a saddle between them, completely encrusted with yellow sponges, are the prime spot to find frogfish doing their camouflage thing, he says. Also look for a little cave in the saddle, where scores of lobsters often hide.

Dive Report

More than 138 lionfish were removed from Saba reefs during Sea Saba’s first-ever lionfish derby in April, reports Nuttall. Catch from the event made for quite the feast at a local restaurant. And recent dives have brought in bigger sightings too, he says, including a 12-foot tiger shark spotted at a dive site called Customs House. Nuttall also says four great hammerheads were seen recently at other sites around the island.

Plan a Trip

Fans of nudibranchs like to dive Saba during the summer months, when the weather calms down and the seas flatten, says Nuttall. These conditions make them easier to spot. The island’s windward sites also become more accessible during the summer months, with colonies of elkhorn and other endangered corals to admire.

Second-Time Visitor

Nuttall points to Tent Reef as one site to make sure you hit if you missed it your first time in Saba. This diverse and healthy site has boulders, shallow reefs, canyons, a mini wall and swim-throughs, as well as sandy patches with garden eels and sea grasses that draw turtles galore. Tent Reef is a local night-dive favorite too.

Cozumel

Under the Radar

After night falls, head out with Salty Endeavors Scuba Center for a Cozumel black-water dive to remember, says owner Henry C. Schulz III. “The middle of the ocean in the middle of the night is a deep, dark and spooky world,” Schulz says. “For 90 minutes you will swear you have left Planet Earth as alien life forms your mind cannot conceptualize,” appear in the bright lights illuminating them in the inky depths.

The Classic Dive

Palancar Reef is a must whether you’re diving for just a day or longer, says Jorge Marin, of Cozumel Marine World. In around 80 feet of water off Cozumel’s southwest coast, the reef stretches across 3 miles and is a drift-diving favorite where you’ll likely see turtles and sharks, for starters.

Dive Report

Nina O’Donovan, of Aldora Divers Cozumel, says regular trips to Cozumel’s far northern reefs have been extra fruitful of late. “We’ve been seeing huge numbers of eagle rays, reef sharks, dolphins, even bull sharks, as well as encountering the reef sharks when they are ‘sleeping’ and in a catatonic state,” she says. “Fantastic dives!”

Plan a Trip

Seeing a single eagle ray is lovely. But for a chance at greater numbers, plan a trip for December to March, when spotted eagle rays migrate through Cozumel’s waters and several can usually be seen on a single dive at Eagle Ray Wall, says Hanns Lampé, of Pro Dive International. Hammerheads, their main predator, have been known to show up here too. O’Donovan points to the summer months on Cozumel’s east side as prime time to spot loggerhead and green sea turtles on dives since it’s nesting season.

Second-Time Visitor

Climb aboard a 4x4 and adventure to Punta Molas Lighthouse on Cozumel’s far northern point during a beach cleanup tour with Lighthouse Project Cozumel that also includes visits to Mayan ruins. The tour departs in the afternoon, so you can still clock two tanks in the morning before doing your part to help keep plastics and other trash out of the ocean.