Green Rock
| Rating | Open Water |
|---|---|
| Depth | 4-28m |
Marine life at Green Rock...
One of the most unique dive sites around Koh Tao, Green Rock is a striking cluster of granite boulders forming swim-throughs, caverns, and narrow passages that invite exploration at every turn. Depths range from around 6 meters down to approximately 28–30 meters, making it an excellent site for both newer divers and experienced explorers who enjoy a more interactive underwater landscape.
Currents & Conditions
Generally sheltered and diveable in a wide range of weather, Green Rock often enjoys good visibility between 10–25 meters. Conditions are typically calm, though mild currents can occasionally sweep through the channels — often bringing increased fish activity. Water temperatures remain a comfortable 27–30°C throughout most of the year.
Underwater Landscape & Marine Life
Green Rock is all about adventure. Its maze-like terrain creates a natural underwater playground, with multiple swim-throughs and hidden chambers that give every dive a sense of discovery. The site is famous for its resident triggerfish — particularly titans & yellow margins during nesting season — making thorough dive briefings essential. When respected, these fish are fascinating to observe and add a pulse of excitement to the dive. Look closer among the rocks and you’ll find blue-spotted stingrays resting on sandy patches, moray eels peering from crevices, and curious groupers shadowing divers. Schools of yellowtail barracuda frequently hover in the water column, while fusiliers and trevally bring constant motion to the reef. Macro lovers are rewarded too, with nudibranchs, shrimp, scorpionfish and well-camouflaged pipe fish tucked into the granite contours. In short, Green Rock delivers variety, personality, and just the right amount of thrill.
Skill Level & Certification
Open Water divers can comfortably enjoy the upper reef and many of the site’s signature features. However, Advanced Open Water certification (or higher) is recommended for divers who want to explore the deeper sections and navigate the more intricate swim-throughs with confidence.
Access & Logistics
Located just a short boat ride from Koh Tao, (15 minutes) Green Rock is perfectly suited to a relaxed morning schedule while still offering a dynamic dive experience. We meet at 7:20am and typically return by 12:00pm. We dive Green Rock once sometimes twice a week as a second dive on our way back from Chumphon Pinnacle. Conditions are generally favorable except from June to August & from mid November thru to early January where big waves prevent us from diving here.
