Diving in the Southern Islands of Thailand

The Hin Muang diving site, the southernmost one, is undoubtedly one of the most incredible ecosystems in the Andaman Sea.

Alone and in the middle of a vast ocean expanse, the two pinnacles start at 16 meters below the surface and descend beyond 60 meters in depth. They are completely covered with soft corals, predominantly in shades of purple. The diving at Hin Muang revolves around the two pinnacles, in a circuit resembling a figure 8 or a 3, depending on the direction of the current or its absence.

A large number of reef species inhabit the two pinnacles: invertebrates such as boxer shrimps, octopuses, or nudibranchs; small fish like thousands of glassfish, groupers, or giant moray eels – there’s a little of everything. In the 20-30 meter zone, you may spot stingrays and reef sharks, while above, there are schools of barracudas and rainbow runners.

Oceanic species can appear at any moment in the magical blue of the Andaman Sea: eagle rays, tuna, large manta rays, and whale sharks during the migration season, between the months of November and May.

The astonishing Hin Daeng dive site – red rock – is located just 300 meters east of its sister site, Hin Muang. Three triangular rocks barely emerge from the water like tropical icebergs, with the largest part hidden below the surface, featuring an incredible drop-off descending to a depth of 50 meters and a gently sloping coral garden.

The rocks are covered with hard and soft corals, predominantly in shades of red and purple, as well as anemones. They shelter hundreds of isolated or schooling reef fish species, such as wrasses, surgeonfish, angelfish, parrotfish, fusiliers, and breams, as well as numerous colorful invertebrates. The diving at Hin Daeng is usually done in two separate dives, depending on the direction of the current or its absence:

Between November and May, the migration of large pelagic species, manta rays and whale sharks, offers an opportunity to encounter them during the dive at Hin Daeng. In summary: Hin Daeng offers a great variety of marine life, quality, and richness, comparable to that of the Similan Islands and Surin Islands archipelagos.

Part of the wonderful Koh Haa archipelago – meaning the 5 islands in Thai – a group of sedimentary limestone islets, the Koh Haa Lagoon diving site is one of the most beautiful and easiest to explore. Koh Haa Lagoon is located between 2 islets, with a secluded cove just in front, housing one of the smallest but incredibly paradisiacal white sandy beaches!

The diving at Koh Haa Lagoon is done around one or 2 of the islets at depths ranging from 5 to 18 meters. It harbors numerous endemic species: ghost fish, seahorses, harlequin shrimp, as well as pairs of seahorses not typically seen at this latitude. Although their color blends with the sand, their gender dimorphism makes them easy to recognize: the female, with a hooked and dark snout resembling that of an eagle, and the male with a flat and clear duck-like snout, following one another.

The night dive at Koh Haa Lagoon, one of the most colorful, is a real must on the cruise circuits in the Southern Islands.

The Koh Haa Cathedral diving site is located on the southwest side of Koh Haa Yai island. It is the largest underwater cave in the sedimentary limestone archipelago, formed through erosion over time. Unique for its brightness, contrasts, and interplay of colors, it is a very special dive not to be missed.

The diving at Koh Haa Cathedral is in a shallow, calm, and clear area. Coral blocks form a garden all around the main entrance of the cave at 14 meters. Two communicating chambers make up this cave, which remains connected to the surface during very low tide.

The interior volume and presence of stalactites create the sensation of a magical place illuminated by a geometric and crossed set of bluish rays. Inside, a school of batfish constantly circles around the divers. For photography and videography enthusiasts, wide shots have an exceptional rendering.

Located north of the Southern Islands archipelago, these diving sites are essential. It is common to observe leopard sharks and blacktip reef sharks here. The King Cruiser wreck, a ferry that sank in 1997, is now covered in colorful soft corals and has become the habitat for thousands of fish over the past decades.

The main attraction here, in addition to the sharks and large schools of tropical fish, is the density of colorful soft corals adorning this massive limestone pinnacle. The reef can be divided into three main sections, and most divers could spend several days exploring the many interesting facets of the site, which is undoubtedly the most popular day diving excursion.

The King Cruiser Wreck, an 87-meter ferry that used to shuttle between Phuket and Phi Phi, sank in 1997 after hitting Anemone Reef, making it the largest artificial reef in the area. It lies on its right side at 32 meters deep, and the top is at 16 meters. Over the past two decades, coral life has abundantly developed, and the wreck is now covered in colorful hard and soft corals, supporting many common reef species.

The King Cruiser dive is a beautiful exploration for wreck enthusiasts, with easy and safe penetration through large openings where surprises await inside… It is an incredibly surprising dive, and the incredible density of fish schools constantly swirling around the wreck can sometimes even obscure the brightness.

The Shark Point diving site is one of the main reefs between Phuket and Koh Phi Phi, along with Anemone Reef and King Cruiser. A true marine sanctuary, the site got its name from the presence of leopard sharks resting on the sandy bottom surrounding the reef. Today, this spot is rightfully one of the most famous local diving sites. Shark Point appears as a tiny rock in the middle of the sea, with a small lighthouse on top for navigation safety between the islands.

Below the surface, the rock formation is covered in pink, blue, and violet alcyonarians, as well as giant orange gorgonians, where marine life is omnipresent: clownfish, groupers, snappers, angelfish, fusiliers, surgeonfish, parrotfish, butterflyfish… The Shark Point dive is conducted around the reef in its south/southeast axis and ends by circling the reef at shallow depths. There is an alignment of coral blocks descending to 26 meters, where spotted blue rays are frequently observed.

This is one of the best underwater dive sites between Phuket and Phi Phi Islands. Submerged at 3 meters below the surface, its shape resembles a small Richelieu Rock. In the first meters, you’ll encounter an immense field of anemones, like a thick carpet, where entire colonies of clownfish have taken up residence. Just below, marine life thrives: turtles, cuttlefish, pharaoh squids, seahorses, zebra moray eels, lionfish, nudibranchs, crustaceans.

The Anemone Reef dive takes place between 5 and 24 meters. Around the rock formation with its pink and purple colors, there is a wide area of clear sand where spotted blue rays are often encountered, and sometimes leopard sharks. The most interesting zone remains the 15-meter mark due to its density and variety of tropical marine life: orange gorgonians, alcyonarians, glassfish, celestial groupers, schools of small breams, barracudas, and sometimes, during the migration season, whale sharks make a stop here.