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Thailand’s: Best 6 Dive Sites


Thailand's stunning Coral
Thailand's stunning Coral

Thailand’s best dive sites lie off the west coast of the Thai Peninsula in the Andaman Sea, north of Phuket in the Similan and Surin Islands, and south of Krabi near Koh Lanta. Here are our Top 6.

Richelieu Rock

This horse-shoe-shaped bommie consists of a huge central pinnacle surrounded by smaller rocks, every inch of which has been colonised by something: soft corals, anemones, barrel sponges and sea fans and almost obscured from view by clouds of glassfish and basslets. In the surrounding blue, look out for manta rays, huge grouper and large schools of barracuda, bat fish and snapper. All of this before you even begin to explore the fascinating smaller creatures lurking in every nook and cranny.

Koh Tachai Pinnacle

Often visited enroute to Richelieu Rock from the Similan Islands, Koh Tachai is surrounded by several dive sites this island has several nearby dive sites, the most spectacular of which is Koh Tachai Pinnacle. As the name suggests is a submerged plateau of hard corals and boulders. Typical of the diving in the Similans, there are swim-throughs and channels all over the place. Larger fish include manta rays, huge schools of swirling chevron barracuda and large numbers of tuna.

Koh Bon Pinnacle

This is a separate range of pinnacles a few hundred metres to the northwest of Koh Bon Island itself. The shallowest pinnacle starts at 18m and is subject to strong current, so this is a site for experienced divers. Across the top of the colourful coral covered rocks there is a good chance of Napoleon wrasse, hunting trevallies and manta rays, while down in the deeper areas you can look for sleeping leopard sharks and blotched fantail rays.

Koh Ha Yai

The diving highlight at Koh Ha is a series of fascinating caverns which are located at Koh Ha Yai, the largest of this group of five (ha) islands. The caverns have large entrances and are safe to enter. In some you can surface inside and see the ancient stalactites which hang from the cave ceiling. Sunrise is a magical time to dive here as the sunlight creates a gorgeous emerald colour.

Hin Daeng (Red Rock)

This is a submerged boulder pinnacle where, looking at the bare rocks above water, you would have no idea that it is such a beautiful dive site below water. Healthy soft corals in various shades of red are all around here and plenty of small-scale action goes on. In the blue, look for large schools of trevally and if you’re lucky, the odd whaleshark and mantas.

Hin Muang (Purple Rock)

Here you will find Thailand’s highest vertical wall, bejewelled with vibrant purple soft corals. One side of the submerged rock levels out at around 60m and the other disappears into the abyss. Vast carpets of anemones cover shallower sections of the reef while sea fans cling precariously to the steep walls. The site is good for big fish, but also for macro life.

When to dive: Diving in the Andaman Sea is between November and April when the weather is at its most stable. During the rainy season (May-October) the Western Monsoon, together with the rain, can bring rough seas, and the national parks close for the season.

Diveplanit has a number of group liveaboard trips planned to the Similan and Surin Islands in the 2023/2024 season. To find out more, contact us: Ph. 1800 607 913 Email.

School of fish over coral
School of fish over coral

This article was originally published in Scuba Diver ANZ #57.

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