Dive and Snorkel Sites

Home Reef

Maratua Island

Maratua is a horseshoe-shaped atoll with coral reefs fringing its edges and limestone slopes dropping over 200 metres into open water. The deep-water channels connecting the inner lagoon to the ocean create strong, multi-directional currents — which is exactly what draws the marine life. With over twenty dive sites across the island, conditions and character vary considerably from one side to the other.

The Channel is a negative entry dive. Rather than spending time at the surface and risking separation by the strong surface currents, divers backroll and drop straight down to the wall at around 25 metres, then move gradually into the channel. Once inside, the goal is to find a position to hold — wedged into the reef or settled on the bottom — and watch. Water rushing through the channel drives the reef into action: chevron barracuda form their famous spiralling tornado in the water column, while trevallies, groupers, and surgeonfish work the current below. It’s a dive you anchor and observe rather than swim through. Certification and prior drift diving experience are required — speak with the dive team before including The Channel in your itinerary.

Turtle Traffic earns its name: green and hawksbill turtles visit the shallow reef flats in numbers to use the cleaning stations, and the site is accessible to snorkellers when conditions allow. Lighthouse Reef is the spot for manta encounters during the winter season, while Fusilier Paradise offers similar wall and blue-water diving with dense schooling fish.

On the outer reef, East Wall drops steeply into open blue water. Black corals grow at depth, and for those who know where to look, the remains of a submerged WWII Japanese watchtower sit embedded in the wall — one of the more unusual things you’ll find on a reef dive anywhere. Mid Reef is the thresher shark site; encounters depend on water temperature and cold-water upwelling, but when conditions align it is exceptional.

Fringing coral reefs and deep-water drop-offs surrounding Maratua

Day Trip

Kakaban Island

Kakaban’s outer reef is a serious dive in its own right. Oceanic walls drop to 200 metres, and the pelagic activity is high. Barracuda Point is one of the few sites in the region with consistent reports of hammerhead and leopard shark sightings. Kelapa Dua is a second thresher shark site, with conditions similar to Mid Reef on Maratua.

But the island’s most unusual feature is entirely separate from its reef. Danau Kakaban is a landlocked marine lake covering nearly two-thirds of the island’s interior — cut off from the open ocean long enough that the jellyfish living inside it evolved without stinging capability. Four species — moon, spotted, box, and upside-down — exist here in enormous numbers. Swimming through them is one of the genuinely unusual experiences available anywhere in the region.

The lake is snorkelling only; scuba is prohibited below 15 metres due to anoxic hydrogen sulphide layers in the deeper water.

The stingless jellyfish lake of Kakaban Island

Day Trip

Sangalaki Island

Sangalaki’s headline attraction is reef manta rays, which patrol the nutrient-rich waters around the island year-round. The terrain is gentler than Maratua — gently sloping from sandy bottoms and coral steps down to around 24 metres — which makes it accessible across a range of experience levels and a good option for those who want productive diving without strong currents. Snorkellers do well here too.

The island is also one of the most significant green turtle nesting grounds in Southeast Asia. Dozens of nesting turtles arrive on the beaches each night, and the underwater population reflects this — encounters in the water are frequent and unhurried. It’s the kind of dive where you slow down and let things come to you.

Nutrient-rich waters home to manta rays and green sea turtles

Special Excursion

Talisayan — Whale Shark Encounters

Talisayan, on the East Kalimantan coast, is where whale shark trips depart from. Traditional wooden fishing platforms called bagans use lights to attract baitfish overnight, and whale sharks follow. Trips leave early — around 4:30am — to reach the bagans before the fish disperse with daylight. It’s a very different kind of encounter from reef diving: open water, pre-dawn, and entirely dependent on what kind of night the bagans have had. When it works, it’s unlike anything else in the region.

On Land

Beyond the Water

Teluk Harapan village is on the resort’s doorstep and worth a wander in the evenings — food stalls, a working fishing jetty, and the kind of unhurried pace that makes it easy to spend an hour doing nothing in particular. Spinner dolphin pods pass along the coast most days and can often be spotted from the shore.

Goa Gumantung sits at the border of Teluk Alulu and Teluk Harapan villages, about 15 minutes on foot along a jungle track and wooden bridges. The cave contains an underground lake with clear water — visitors take a rubber boat across around 100 metres of it. The name comes from the swiftlet nest harvesters who used to scale the cave walls; these days people come for the swimming and the cool, still atmosphere.

Goa Halo Tabung is a karst cave about 50 metres from the shoreline, with a conical interior dropping 25 metres into a cold, brackish pool fed by seawater filtering through the rock. The cave ceiling splits into two sections, forming a natural passage that swimmers can move through. The water is exceptionally clear — you can see the cave floor easily. Stairs are provided but the rock is steep and slippery; good footwear and care are needed.