HTMS Sattakut Wreck

The HTMS Sattakut is Koh Tao’s most accessible wreck dive — a 50-metre former US Navy vessel (commissioned as a landing craft, later transferred to the Royal Thai Navy) intentionally sunk in 2011 to form an artificial reef. In the years since, it has been progressively colonised by hard and soft corals, sponges, and a resident population of marine life that makes every dive here rewarding.

The Wreck

The vessel lies on its side at a depth of 17–30 metres, making it suitable for divers from Advanced OW level and above. The superstructure is now heavily encrusted with corals and sponges, and the interiors — accessible through open hatches and windows — host some impressive residents. Giant moray eels occupy the darker recesses, lionfish hover near every overhang, and scorpionfish merge imperceptibly into the coral-encrusted metalwork.

Schools of batfish and fusiliers orbit the wreck permanently, and groupers of impressive size claim territories around the larger structures.

Penetration

For divers with the appropriate training, the HTMS Sattakut offers some excellent penetration opportunities. The bridge, engine room, and main hold are all accessible and well-documented by local dive guides. Penetration should only be undertaken with a qualified guide familiar with the wreck’s layout.

Night Diving

The Sattakut comes alive at night. Octopuses emerge from crevices to hunt, cuttlefish prowl the exterior, and the lion and scorpionfish — cryptic and hard to spot by day — become actively visible. One of Koh Tao’s best night dive options.