Diving sites now figure prominently in the popularity of both the Gulf of Thailand and Andaman Sea, with both areas rated among the best in the world.

Thailand's underwater natural heritage is a breathtaking complement to the beauty of its islands. Ko Tao and Ko Samui both have booming diving industries, and are especially excellent for the beginner who would like to learn diving first-hand in the sea.

Ko Tao offers enough excellent instruction that the beginner can move to the expert level without ever leaving the island. With most industry on the island being simple and with few large hotels, Ko Tao offers a pristine diving location.

Phuket is the diving center of the Andaman Sea, and offers similar training for the novice diver, and dive experiences as varied as the surround- ing islands themselves. Primes sites in the vicinity of the island itself are Shark Point, Hin Daeng, Ko Yao, Ko Hai and Ko Raja

Dive experts - charter boat captains, marine biologists, dive book authors - consider the coral of Surin Islands National Marine Park to be the best in Thailand. A national park since 1981, off Phang Nga province, the five-island cluster has a spectacular array of pristine live coral formations. A prime dive spot is the channel between the two main islands of north Surin and south Surin. Other favorite dive sites are the southeastern point of north Surin, Ko Chi off the northeast coast and Richelieu Rock, a sea-mount southeast of south Surin. Whale sharks are commonly sighted near Richelieu.