Thailand is a country filled with sandy beaches, and hundreds of beautiful islands, found on the east side in the Andaman Sea, and on the west side, in the Gulf of Thailand. While not as popular at the better known Andaman Sea, diving in the Gulf of Thailand has some definite treasures! The area is somewhat sheltered and that protection allows for diving year round; many find the best diving conditions in the Gulf from May to October.
The most famous site in the Gulf is Hin Bai – more commonly referred to as Sail Rock. This pinnacle sits between Koh Phangan and Koh Tao, and as it is the only structure in the area, it tends to attract lots of life – particularly some really big fish! Schools of very large trevally are often seen chasing smaller groups of fish, hoping perhaps for an easy lunch. Huge longfin batfish swim next to the rock, often peering inquisitively at the scuba divers. Keep your eyes open to the blue; you might get lucky and see large pelagics, maybe even a whale shark.
Between Koh Phangan and Koh Tao to the north, there are several other pinnacles with great diving. Southwest Pinnacle, Samran Pinnacle, Shark Island are all easily accessible. Near to Koh Phangan are local dive sites at Koh Maa, which is great for all levels of diver, and home to many different types of coral and a huge anemone garden (full of Nemos!). And of course to the west, the picturesque Angthong National Park, consisting of 42 islands and known for its abundance of soft corals, underwater caves, swimthroughs and abundance of marine life.
Read more about diving in the Gulf, and other parts of Thailand on the PADI website.