Maratua is the outer atoll of the Derawan Archipelago off East Kalimantan (Borneo), facing the Celebes Sea, and the region's premier big-fish destination — its single reef channel, 'Big Fish Country', holds one of the largest schooling barracuda tornadoes in Southeast Asia alongside resident grey reef sharks riding the current.
Destination info
Conditions, highlights, and the resident marine life.
Conditions
Water and air temperature across the year.
WaterAirDryShoulderWet
Description
Maratua Atoll sits roughly 70 km off the East Kalimantan coast at the seaward edge of the Derawan Archipelago, an isolation that gives it clearer, bluer water than its inner neighbours and brings open-ocean pelagics close to the reef. The atoll's signature dive is 'Big Fish Country' (also called The Channel) on the north shore, where tidal flow surges through a break in the reef: divers hook onto the plateau at the channel mouth around 20–30 m and watch a slowly rotating tornado of chevron barracuda while grey reef and whitetip sharks cruise against the current, with occasional thresher and hammerhead sightings. Beyond the channel, near-vertical walls (Hanging Gardens, East Wall), turtle-thick reefs (Turtle Traffic), and gentle coral gardens round out 20-plus sites. The wider Berau seascape is Southeast Asia's largest green-turtle nesting ground, and dozens of green and hawksbill turtles on a single dive are routine. Water stays 27–30°C year-round and visibility commonly reaches 20–30 m or more. Most diving is intermediate-to-advanced drift diving from shore-based resorts or liveaboards; the channel itself is a strong-current site demanding experience, a reef hook, and a local guide who can read the tidal window. Sangalaki, Kakaban and Derawan lie within a short boat ride.
Highlights
What makes this dive worth the trip.
Maratua's single reef channel, 'Big Fish Country' (The Channel), is home to what many consider one of the largest schools of barracuda in Southeast Asia — a slowly rotating 'tornado' of chevron barracuda. During strong currents grey reef sharks cruise against the flow, and divers hook onto the flat plateau at the channel mouth to watch the show.
The currents through the channel range from challenging to extreme: a reef hook is strongly recommended and the site is best entered on the incoming tide, positioned at the channel entrance around 30 m. One operator declines to dive it outright, citing 30 m+ depth, whirlpools, vertical walls and distance from medical care — Maratua's channel is for experienced divers only.
The Derawan/Berau region is Southeast Asia's largest green sea turtle (Chelonia mydas) nesting area — and the world's eighth largest — with more than 5,000 marine turtles recorded nesting each year. At Maratua's 'Turtle Traffic' site green and hawksbill turtles are abundant, and firsthand reports count more than 40 turtles on a single dive.
Marine life
38 species you’re likely to encounter on a dive here.
Dive sites
8 signature sites at this destination.
Big Fish Country (The Channel)
Maratua's world-famous signature dive, on the north part of the atoll where a break in the reef funnels tidal flow into the lagoon. Divers descend to the plateau at the channel mouth (around 20–30 m), hook onto solid rock, and watch a tornado of chevron barracuda rotate overhead while grey reef and whitetip sharks hold station against the current. Jacks, big groupers, fusiliers, surgeonfish and rainbow runners crowd the channel; eagle rays, mantas, and occasional thresher and hammerhead sharks pass through. The site is entered on the incoming tide and is strictly for experienced divers — the current can range from challenging to extreme, with whirlpools reported, and a reef hook is essential.
12–30 madvancedDay boatVery strongVisibility 15–30 m
Turtle Traffic
A reef site close to the resorts on the lagoon side, named for the sheer number of green and hawksbill turtles that congregate here — hundreds frequent the area and firsthand divers report counting more than 40 on a single dive. Turtles rest beneath table corals and crevices at low tide and glide through the current at other times, which also carries in pelagics such as rays and reef sharks. A gentler, more accessible site than the channel; in good conditions parts of the reef are shallow enough for snorkellers as well as divers.
5–25 mintermediateDay boatModerateVisibility 15–30 m
Mid Reef
An outer-reef site regarded as one of the better chances on the atoll for a thresher shark encounter (luck and good conditions required), as well as nurse sharks, eagle rays, large giant stingrays and big schools of jackfish. The reef slopes into deeper water where the pelagic action concentrates, so it rewards divers comfortable with depth and current and watching the blue.
12–35 madvancedDay boatStrongVisibility 20–40 m
East Wall
A dramatic wall on the seaward (east) side of the atoll, about 15 minutes from the resorts, where a sandy coral slope gives way to a vertical drop plunging from roughly 45 m past 70 m. Extensive sea fans and black corals cloak the wall and eagle rays pass frequently. The site is notable for the remains of a Japanese World War II watch tower on the shore above. A deeper, advanced wall dive best in mild current.
15–45 madvancedDay boatModerateVisibility 30–50 m
Eel Garden
A sandy slope colonised by a dense field of garden eels swaying in the current, backed by varied hard and soft coral. Depending on the tidal flow the site also draws in Spanish mackerel, trevally and barracuda hunting along the reef edge. A pleasant, varied dive that contrasts the channel's intensity with macro and reef interest.
8–30 mintermediateDay boatModerateVisibility 20–35 m
Cabbage Patch (Cabbage Coral Reef)
A short ride from the resorts, this site is built around a football-field-sized formation of cabbage (lettuce) coral on a reef that shelves from about 5 m to 16 m before the wall drops away to 200 m+ offshore. Mild current makes it an easy, accessible dive where turtles, eagle rays and the occasional manta cruise the reef edge. A good check-out and relaxed reef dive on the atoll.
5–18 mbeginnerShoreLightVisibility 20–30 m
Hanging Gardens
A near-vertical wall pocked with overhangs and gullies, draped in black coral trees and sea fans growing in profusion. Reef fish — sweetlips, snappers and angelfish — shelter in the caves and crevices, while looking out into the blue divers regularly see fusilier schools, reef sharks, turtles and, on a good day, schooling barracuda. A scenic wall dive that works across a range of conditions.
8–40 mintermediateDay boatModerateVisibility 20–40 m
Lighthouse
About 20 minutes from the resorts, a reef that slopes to a sandy bottom around 40 m. Mild current and good visibility make it a relaxed dive where schools of batfish hang over the reef and leopard sharks, groupers and red snappers are regular sightings. A gentler counterpoint to the atoll's current-swept channel sites.
10–40 mintermediateDay boatLightVisibility 30–40 m
Where to dive & stay
Local dive centers, resorts, and hotels.
Featured operators coming soon
Verified dive centers, resorts, and hotels around Maratua will list here — pricing, photos, and direct contact.
