Derawan Islands Travel Guide: Mantas, Jellyfish & Turtles in East Kalimantan

The Derawan Islands form an archipelago of 31 islands off the northeast coast of Kalimantan, the Indonesian part of Borneo. They are rarely mentioned in the same breath as Komodo or Raja Ampat among casual visitors, yet among dive professionals and marine biologists the concentration of megafauna here is considered extraordinary — manta rays, loggerhead turtles, whale sharks, and a landlocked jellyfish lake that has no equivalent anywhere in this region. Getting here takes effort, and that effort is part of why it remains in better condition than more accessible destinations.

The Islands

Derawan Island

Derawan is the main base camp and where most visitors stay. It is a small, flat island with a fishing village, a handful of dive operators, and accommodation ranging from basic homestays to mid-range bungalows over the water. The jetty is the most reliable place in Indonesia to see loggerhead turtles at close range — several individuals come to feed near the stilts every night. This costs nothing and requires no boat. The turtles are accustomed to human presence but should not be touched.

Kakaban Island

Kakaban is the scientific highlight of the archipelago. A marine lake trapped inside the island has been sealed from the open ocean for tens of thousands of years, long enough for the jellyfish population to lose their sting. Four species of stingless jellyfish inhabit the lake — thousands of them, in densities that make swimming through them surreal. Entry to the lake costs approximately IDR 50,000 as of 2026, payable at the ranger post on the jetty. The swim from the jetty to the lake entrance takes about five minutes. Fins are not recommended inside the lake itself as they damage the jellyfish.

The outer reef at Kakaban is separate from the lake and considered some of the best diving in the entire archipelago — walls with strong currents, schools of barracuda, and regular manta sightings.

Sangalaki Island

Sangalaki is a protected turtle nesting beach and one of Indonesia’s most significant sites for green and hawksbill turtles. The surrounding waters are a manta ray feeding ground. Mantas gather here throughout the year in concentrations that consistently number in the dozens, with surface feeding sessions observable from snorkel without diving equipment. There is no public accommodation on Sangalaki itself; the island is accessed as a day trip from Derawan or on a package through Sangalaki Dive Lodge.

Maratua Island

Maratua is the largest island in the group and shaped in a long curved arc enclosing a shallow lagoon. The outer walls drop steeply into deep water and attract whale sharks, most reliably between June and August when they surface near fish farming platforms at the northern end of the island. Sightings are not guaranteed, but regular enough through those months that operators on Derawan include Maratua in packages specifically as a whale shark destination. Maratua also has some of the most consistent coral coverage in the archipelago on its eastern wall.

Getting There

The access route requires multiple legs. From most international origins, the relevant routing is:

Jakarta → Berau (BEJ): Garuda Indonesia and Lion Air both operate this route, typically with a transit in Balikpapan or Makassar. The total journey from Jakarta to Berau is approximately 3–4 hours flying time including connections. Fares from approximately IDR 800,000–1,800,000 one way as of 2026 depending on airline and advance booking.

Berau → Tanjung Batu: From Berau’s Kalimarau Airport, take a taxi or ojek to the town of Tanjung Batu (approximately 2 hours, IDR 150,000–200,000 by shared car). There are also speedboat charter options from Berau town directly.

Tanjung Batu → Derawan Island: Speedboats run from Tanjung Batu pier to Derawan Island in approximately 45 minutes, costing IDR 50,000–80,000 per person on public boats, or IDR 400,000–600,000 to charter. Services are not on a fixed timetable; boats depart when full or when arranged.

Some dive packages include all transfers from Berau, which removes the coordination burden considerably.

Accommodation

Budget homestays on Derawan Island start from approximately IDR 200,000 per night as of 2026 for a simple room with fan and shared bathroom. Most include basic meals; the village has several warungs serving fresh fish. These are functional and acceptable for those spending most of their time underwater.

Derawan Dive Lodge sits on the northwest corner of Derawan Island and offers mid-range bungalows over the water with dive packages. Expect to pay approximately IDR 600,000–900,000 per night for a room including breakfast, with dive packages quoted separately.

Sangalaki Dive Lodge on Sangalaki Island operates as an all-inclusive dive resort from approximately USD 150 per person per night as of 2026, covering accommodation, three meals, and two boat dives daily. It caters specifically to diving guests; there is no reason to stay here without diving.

Maratua Paradise Resort is the most upscale option in the archipelago, located on Maratua Island. Rates from approximately USD 100 per night as of 2026. The resort has its own dive operation and speedboat access to all major sites.

Diving and Snorkelling

The Derawan archipelago sits within the Coral Triangle and records some of the highest marine biodiversity in the Indo-Pacific. The concentration of manta rays around Sangalaki and Kakaban is one of the densest documented in Indonesia. Dive sites worth specific attention include:

• Kakaban outer wall: Steep drop-offs, regular manta cleaning stations, hammerhead sightings at depth
• Sangalaki reef flat: Manta feeding, green turtle encounters, garden eels
• Maratua east wall: Large pelagics, whale sharks June–August, current diving
• Derawan house reef: Accessible from the beach, turtles, reef fish, entry-level diving

Dive operators on Derawan Island charge approximately IDR 400,000–600,000 per dive for two-tank boat dives, excluding equipment rental. Full equipment hire adds approximately IDR 100,000–200,000.

When to Visit

April through October is the dry season and the recommended window. Sea conditions are calmer, visibility is at its best (typically 20–40 m), and water temperatures average 28–30°C. Whale shark sightings at Maratua are most consistent in June, July, and August.

November through March brings the northwest monsoon to Kalimantan, with rough seas that can make inter-island boat trips uncomfortable or impossible for several days at a time. Some operators close or reduce schedules during this period.

The jellyfish lake at Kakaban is accessible year-round when conditions permit.

Practical Notes

There are no ATMs in the Derawan archipelago. Bring sufficient cash from Berau — IDR in small and mid-denominations. Card payments are not accepted at most homestays or dive operators.

Mobile signal exists on Derawan Island (Telkomsel works best) but is patchy on the outer islands. Download offline maps before leaving Berau.

The area is a protected marine reserve under the East Kalimantan provincial government. Fishing from boats in certain zones is restricted; anchoring on coral is prohibited. Dive operators are generally responsible about these regulations, but it is worth confirming their practices before booking.

Bring reef-safe sunscreen — chemical sunscreens are prohibited near the jellyfish lake and discouraged throughout the marine park.