Qualified Instructors
The Gulf of Thailand and the Andaman Sea possess superb dive sites, as many guidebooks will testify. Diving gear and PADI/NAUI instruction are available from dive shops on every major island and coastal resort. Instruction costs roughly US$250-330 (with equipment) for full qualification and is mostly in English or German, with several other languages in larger centers.

Year-round Diving
Diving in the Gulf is generally all year round: Pattaya is the foremost diving center due to its close proximity to Bangkok. Visibility here is often poor, but at smaller islands nearby it is much better – 3 to 9 meters at most sites, more at those farther out. Excursion prices start at around US$50 for two dives with gear, guide and lunch all included. For this you can see natural and artificial reefs – shipwreck prices are higher. Non-divers can usually join dive trips for a discount of 30-50%. Other good centers along the eastern side of the south coast are Koh Samui, Koh Phangan and Koh Tao.

Prime Locations
Phuket is the main dive center in the Andaman Sea, with most dive shops concentrated around Patong Beach. Other areas are easily accessible from Phuket: the beautiful bays of Krabi and Phang Nga are just an hour or two away by boat. The Similan and Surin island groups take longer to reach, but the marine life (including manta rays and the occasional whale shark) and stunning coral reefs are well worth the trip. December to April is the best diving season here.