Some of the best dive sites in the world lie off the coast of Phuket in the Andaman Sea. Due to its modern infrastructure and year-round safe anchorages, Phuket is the obvious gateway to the marine national parks in Western Thailand and the Mergui Archipelago in Burma.

The most famous dive sites are in and around the Similan Islands, about 60nm northwest of Phuket. These nine islands offer the clearest water, the whitest coral-sand beaches, and the most colourful marine life in the Kingdom. The diving environment ranges from huge boulder outcroppings, to gently sloping healthy coral reefs, to deep submerged pinnacles. To the north, near the Myanmar (Burma) border, lie Koh Bon, Koh Tachai, the famous Richelieu Rock, and the Surin Islands. Each is a unique environment, well worth the extra effort to visit.

Travelling north past Richelieu Rock, you will arrive at the Mergui Archipelago, historically part of Thailand (Siam), now governed by Myanmar. A remarkable group of over 800 islands, the archipelago has only recently opened to tourism following almost 50 years of closure. With over 10,000 square-miles of calm seas and uninhabited islands, the diving and water sport possibilities here are almost immeasurable. However, the dive sites and islands lie far from any major port, and supplies are not available, so a visit to this area requires more days at sea and forward planning.

Four hundred and fifty miles to the northwest are the Andaman and Nicobar Islands, a part of India. This area is much like it was 100 years ago with very little deforestation and almost no active fishing. However, permissions for dive boats are difficult to obtain, and distances between dive sites vast. Thus, lots of pre-planning and at least two weeks of your time are necessary to visit these islands. It’s well worth it if you have the time and money though.

Manta rays and whale sharks commonly visit the Andaman Sea throughout the year. In addition, dive sites are home to hundreds of rare marine species not found in other areas of the world, including pipe fish, sea horses and nudibranches.

Diving around the southern parts of Phuket is also beautiful. Famous, popular places such as Shark Point and the Phi Phi Islands offer incredible diving on most days. Day-trips are fun to these sites, while the other areas mentioned above generally require a multi-day liveaboard trip. However, Similan Island day-trips are gaining in popularity with recently introduced faster dive boats.

It is impossible to see all that Thailand, Myanmar and the Andaman Islands have to offer in just one trip. People return repeatedly in order just to get a taste of it. Whether you have only a day or a few weeks, make time to dive our Andaman Sea, one of the world’s treasures.

Diving section contributed by John B. Williams.

John Williams is the author of three dive guides on Thailand, Burma, and the Andaman Islands including the recently published Lonely Planet Diving and Snorkelling Thailand. For more information about diving in the Andaman Sea, please visit his website at http://www.siamdivers.com or email him at john@siamdivers.com.