Three islands. Three different roles.

The Derawan name covers an archipelago of about thirty islands, but for divers only three matter: Derawan Island itself, Sangalaki, and Maratua. They sit within a triangle roughly 50 km on each side, all reachable by speedboat from each other in 60-90 minutes.

Most first-time visitors get this wrong. They book accommodation on Derawan Island (where most flights and ferries arrive), then realize the best diving is at Sangalaki and Maratua and spend their days commuting. The pattern below saves you that mistake.

Derawan Island — the gateway, not the destination

Derawan Island has the airport-adjacent infrastructure: a few homestays, two restaurants, the harbor where the speedboats dock. The diving here is decent but secondary — the house reef has good macro (mantis shrimp, frogfish) but no manta cleaning station.

What to do here: arrive, sleep one night if your flight schedule requires it, then leave. Don’t structure your trip around Derawan Island.

Sangalaki — the manta island

Sangalaki is the smallest of the three, a 22-hectare island ringed by reef. Its claim is Manta Point — a cleaning station roughly 800m off the southwest beach where reef manta rays gather year-round. Sightings are reliable (we estimate 80% on a single morning dive, 95% over two attempts).

It’s also Indonesia’s largest green turtle nesting beach. From March to October, you can join a WWF ranger walk at night and watch nesting females, then hatchlings in the morning at the right time of cycle.

What to do here: 1-2 days, 4-6 dives, ranger turtle walk one night. Single eco-resort on the island; book 4-6 months in advance.

Maratua — the wall island

Maratua is by far the largest (380 km²) and has the most varied diving. Big Fish Country is a current-driven channel where schooling barracuda form tornados; Reef Garden is a gentle muck-and-coral mix; and the wall at the southeast tip drops to 1,000m+ within finning distance of shore.

Maratua is also where most boutique resorts are located — Nabucco, Maratua Paradise, plus a handful of homestays. Mobile signal exists but is patchy; bring offline maps.

What to do here: 2-3 days, 6-9 dives. Day-trip from here to Kakaban (jellyfish lake) and Sangalaki (manta).

Kakaban — the jellyfish lake (snorkel only)

Kakaban is uninhabited. Its central lake is a former marine basin closed off by tectonic uplift, now a brackish saltwater lagoon containing roughly 60 million stingless jellyfish. The species evolved in isolation for ~5,000 years and lost their stinging cells. You snorkel among them. There is no diving (lake floor has no oxygen).

Day trip from Maratua, 2-3 hours including transit. Bring sun protection — there’s no shade on the island. Sunscreen wash-off is banned (it kills jellyfish); bring rash guards instead.

The right pattern

Sleep in Maratua. Dive Maratua + Sangalaki. Day-trip Kakaban once. Skip Derawan Island except for transit. You’ll come home with the right photos.