Derawan & Sangalaki

The islands are far enough apart that a day is planned around boat runs rather than sites. From Derawan, Sangalaki and Kakaban are open-water crossings in a fast boat, so a typical day is two dives out and one on the way home, with surface intervals spent aboard or on a beach. Operators based on Maratua have the walls on their doorstep and run shorter trips instead. The bases differ in feel as much as in position: Derawan is a working village with guesthouses and warungs, while the Maratua resorts are largely self-contained.

Nothing here is deep, and each island dives differently. Derawan's shallows are seagrass, sand and low coral where turtles graze and small subjects sit in the rubble under the jetty, and it is the easiest place to simply walk in. At Sangalaki the technique is to settle on the sand at the edge of the shallows and stay put, since swimming after a feeding ray is the reliable way to lose it. Maratua is the outlier: a fringing wall along the atoll rim with a channel into the lagoon, where tidal exchange sets up drifts and fish stack at the corners.

The plankton that brings rays in to Sangalaki is also what greens the water, so visibility swings between sites and days and wide-angle work has to be planned around the animals rather than the conditions. Kakaban is dived on its outer wall, while the lake sits inside the island rim, reached on foot up a plank staircase and down a boardwalk, and is usually fitted into a surface interval. The area suits divers who want turtles, rays and an unpolished island trip more than reef spectacle, and who accept that a fair share of the holiday goes on getting there.