

Best for intermediate divers, 13-24m, boat entry, moderate current.
HTMS Hanhak Sattru is a decommissioned naval vessel resting at depths between 13 and 24 metres near Koh Nang Yuan. As an artificial reef, the wreck features a complex superstructure that requires steady buoyancy control due to moderate currents. Visibility typically ranges from 14 to 30 metres, allowing for clear views of the vessel. The site includes enclosed sections that present an overhead environment, necessitating caution and the use of a dive torch for those entering the hull. This site is suitable for intermediate divers, with boat access required for all visits. Night diving is available, offering opportunities to observe nocturnal activity within the structure.
10.09270, 99.85430
Book a guided tour for your first visit, as a guide familiar with the wreck layout will help you navigate safely inside the structure and identify the best spots where fish congregate. Night dives here are worth planning ahead, as the crustaceans and nocturnal reef fish that shelter in the hull become far more active after dark.
Access is via boat from Koh Tao, often departing from Hin Wong Pier.
Recorded at this site
Depth
13-24m
Visibility
14-30m
Skill Level
Intermediate
Entry
Boat
Boat required
Water Temp
28-31°C
Current
Moderate
Typical Dive
50 min
Best Time
May, Jun, Jul, Aug, Sep
The wreck rests at depths ranging from 13 to 24 metres, with an average depth of 20 metres.
No, this site is rated for intermediate divers due to the overhead environment of the wreck and the presence of moderate currents.
The site is located 60 metres from shore and requires boat access.
This site is primarily a wreck dive located at depths starting from 13 metres, making it unsuitable for snorkelling.
Water temperatures are consistent year-round, ranging between 28°C and 31°C.
Diving at HTMS Hanhak Sattru in Koh Tao requires the following certifications: Open Water, Advanced. Always dive within your training limits.
A rashguard or 2mm shorty is recommended for diving at HTMS Hanhak Sattru in Koh Tao. Water temperatures range from 28°C to 31°C.
The best months to visit HTMS Hanhak Sattru in Koh Tao are May, June, July, August, and September. Conditions outside these months can still be good but are less predictable.
Divers at HTMS Hanhak Sattru in Koh Tao should be aware of lionfish. These encounters are generally rare and avoidable with proper awareness. Follow local safety guidance and maintain a respectful distance from all marine life.