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Liveaboard Diving in Phuket Surrounding Provinces

Best Dive Sites in Phuket Surrounding Provinces

Both to the northwest and southwest lie the best dive sites Thailand has to offer. To the northwest lie the marine national parks of Similan and Surin Archipelagos which are referred to by local dive shops as North Andaman. These dive sites are well offshore and can be visited by speedboats for the day from Thap Lamu harbour north of Phuket, but the more common and better way to see them is by joining a liveaboard boat for a 2-10 day trip. Liveaboards are like small cruise ships where you sleep and eat and dive from a boat. This allows three or more dives per day, including night dives, as you don’t have travel time to spoil your schedule because the boats moor very close to the sites and either move between dives during the surface interval or longer distances are travelled at night while you sleep.

To the south of Phuket, we have famous sites such as Koh Ha, Hin Daeng and Hin Muang. This area is called South Andaman. These sites can be dived as day sites from Koh Lanta and sometimes from Phi Phi Island, but if you’re in Phuket, your best choice is again a liveaboard boat. Some longer trips do the whole “Best of Thailand” route, which includes both North and South Andaman.

These popular marine national parks are open each year from Oct 15th until May 15th. The rest of the year, they are closed and off-limits to everyone.

1. North Andaman Dive Sites

andaman diving

The Similan Islands archipelago is by far the most beautiful group of dive sites that we have in Thailand and one of the best diving spots in Southeast Asia. The Similan Islands are located about one hundred kilometres northwest of Phuket. They feature nine granite islands covered in a tropical jungle, washed by the clear blue Indian ocean and blessed with some of the world’s finest beaches. Similan comes from a Malay fisherman who named it “The Nine Islands.” Similan is “nine” in Yawi, a South Thai-Malay dialect.

The islands are identified by a name and a number, one through nine. The islands are part of the national park status and are fully protected under Thai law. The National Park Authority maintains its presence on two of the islands: Koh Similan (Island 8), the largest, and Koh Miang (Island 4). There are basic bungalows and camping on Island 4.

The West Coast offers fast-paced, exhilarating diving as currents swirl around the huge granite boulders, some larger than the largest of houses. These smooth rounded boulders create formations, forming holes and overhangs or swim-throughs underwater where divers can enjoy ducking and kicking through the openings. The drama of looking up through the clear water at these huge rocks is satisfying enough for some divers, as there are very few places like this on earth. Growing on these boulders are some of the most colourful soft corals imaginable, in many places so thick that the rock is no longer visible. In the larger passages or channels between the boulders, the orange sea fans characteristic of Similan grow to three or four meters across and are often so tightly bunched together that they block passages.

The East Coast once offered healthy coral down white sand slopes, but the coral bleaching event of 2010-2011 severely impacted these corals. Many of the eastern dive sites are closed to the public to allow them a full recovery. In a few areas, especially around Island 5, you’ll see what it looked like before and what it will look like again one day. You’ll be doing some of your dives on the east side of the islands for sure, but not as many as you once would.

If you enjoy watching and photographing tropical fish, the Similan Islands are hard to beat for the sheer numbers and varieties of tropicals, especially lionfish and anemone fish. The Similans are not well-known for big fish action, but we do see giant trevally, some Napoleon wrasse and turtles. Of course, the most famous aquatic resident of Thailand, the leopard or zebra shark, makes his appearance on a regular basis. As the park becomes more and more protected from fishing, fish sizes are increasing. Overall, in my opinion, reef fish are 20-30% larger on average than they were 30 years ago when I started diving here.

We’ll also see white-tip and black-tip sharks, and a few times over the years, we’ve seen schools of pseudo orcas or false killer whales. We get a lot of dolphins between the islands, moving north and south. Enjoy the Similans for wild, unspoiled beaches, magnificent soft coral, prolific fish life, crystalline blue water and sensational underwater rock formations.

2. Koh Bon

Liveaboard diving near Phuket

Koh Bon is located about 20 km north of Similan Island 9 and features one of the few vertical walls in Thailand. The main dive site is on the southwestern point and has a step-down ridge that carries on to depths of over 45 meters. The eastern side of this ridge forms the wall, and this is where most divers will enter the water and generally where the boats moor. The western side of the ridge is more of a gentle slope with coral bommies forming mushroom-like formations out of the finger corals. On the ridge itself, sea fans of different sizes, shapes and colours grow, and schooling fish swim in the current feeding. This is generally where most divers will sit most of the dive, hoping for a sighting of the manta rays which frequent this dive site. These creatures seem to travel from Bon to Tachai and back again.

Leopard sharks are pretty common below the ridge on the sandy flats. Although the soft corals are not as high-profile as they are in the Similans, the colours of the corals are radically different and include shades of turquoise, yellow and blue, besides the more common pinks and purples. The colours are more pastel than the usual hard bright we see commonly other places.

Rays will sometimes be found in the deeper areas at depths for more experienced divers. The Koh Bon ridge is full of individual and schooling fish, and some overhangs have places for smaller creatures to hide, but this is more of a fish and coral dive than a critter dive.

Above the waterline, there is a huge hole on the ridge, and when a swell is running, it pushes the water through the hole, and the force of it makes white water below the surface, making for a fun and exciting safety stop. Just don’t get too close to the surface if the swell is big.

There is a pinnacle in the bay just to the north of the ridge. It’s a deep rock, but if you’re an experienced diver, it’s worth the short bottom times you’ll get as it’s a very special site. Not all boats visit it, and if currents are strong, it’s not worth the effort. But, if the water is clear, you’re good with your breathing gas, and the current is slack, it’s a stunning rock. It looks like a monolithic temple built by some ancient culture.

The rock runs along an almost east-to-west course, the taller of the two pinnacles comes up to about 18 meters, and the other pinnacle comes only up to about 24 meters. The sandy areas around the rock are well over 45 m, so beyond the range of most scuba divers. However, when the visibility is good, you see all the way around the rock. Leopard sharks hang here, but it’s also a good place to see smaller critters hiding in the rock. The pinnacle is fairly close to the main ridge, and it’s possible to swim to the ridge, though there is little reason to do so.

3. Koh Tachai

Koh Tachai diving near Phuket

Twenty-five kilometres north of Koh Bon, Koh Tachai has an offshore underwater ridge that runs perpendicular to the island. Known as “Twin Peaks”, this is considered to be one of the finest dives in Thailand and is famous as a place to see not only the more common species of corals, fans and tropical fish but larger animals such as rays, leopard sharks, nurse sharks and hawks bill turtles. Whale sharks and manta rays make an appearance on a regular basis.

A ridge runs between the two pinnacles, though the eastern rock is the one most people dive as there are boat moorings making it easier for divers to descend in a strong current. If you have the gas and the current is not too strong, it’s worthwhile swimming to the other rock, which comes up a bit shallower. However, most of the time, the current runs perpendicular to the ridge making a long swim tiring. It’s heaven for the fish, though; they hunt and dart around, coming very close to divers, making the diving here about as exciting as it gets.

A ridge runs between the two pinnacles, though the eastern rock is the one most people dive as there are boat moorings making it easier for divers to descend in a strong current. If you have the gas and the current is not too strong, it’s worthwhile swimming to the other rock, which comes up a bit shallower. However, most of the time, the current runs perpendicular to the ridge making a long swim tiring. It’s heaven for the fish, though; they hunt and dart around, coming very close to divers, making the diving here about as exciting as it gets.

Koh Tachai also boasts a breathtaking sandy beach on its northeastern shore; It’s a popular anchorage when northeast winds have calmed down in March and April. The beach is one of the prettiest anywhere though it’s not always open.

Some boats offer night dives on the western part of the island in a small bay or in front of the beach, weather permitting. The main ridge is generally too deep, and the currents too strong for reasonable and safe night diving.

4. Richelieu Rock

Liveaboard diving near Phuket

Richelieu has become famous as one of the best places in the world for swimming with our gentle giant, the whale shark. Encounters with the largest of all fish are rare in almost any place in the world. But for some reason, Richelieu attracts more than its fair share. Swimming with such a large animal, known to grow to lengths of 15 meters or more, has to be a high point for any diver. Sightings are up and down, but in the past two or three years, we’ve seen numbers like we did way back in the 1990s. This is encouraging. When they are seen, you generally get a really good look since you’re diving in clear water, and they swim close to the rock. It’s like a parade, a happy parade.

Nearly every imaginable variety of bony fish is found here, including many species of butterfly fish, wrasse, damselfish, lionfish and a host of other reef dwellers. Among the most abundant species are scorpion fish, which are amazingly adept at blending in with their surroundings. Be especially careful where you put your hands because many things that look like rocks are not really rocks! A number of eel species live here as well, including giant, white-mouth, fimbriated, snowflake, bar-tail and zebra morays. Schooling fish like fusiliers and snapper are also prevalent, in addition to open-water predators like rainbow runners, mackerel, and barracudas. One schooling fish deserves special mention–a huge school of bigeye jacks can often be seen on the up-current side of the rock, where they often circle divers en masse, creating a living maelstrom of fish. Schooling chevron barracudas are seen almost all the time.

Divemasters are now quite good at spotting ghost pipefish, Harlequin shrimp, and tiger-tail seahorses–if you don’t see something weird here you just aren’t paying attention. Cuttlefish hover around, usually in the autumn, but very often at other times of the year as well. Octopus is common, and lionfish as well as different kinds of anemone fish.

Richelieu Rock is a world-class dive site, and if you don’t like diving here, you simply don’t like diving! You can dive here over and over and see something new. The currents change constantly, and it’s not always an easy dive. But, if you listen to your dive guide and his or her briefing, you can learn how to hide from the currents and have a very enjoyable dive all the time. Many boats will spend the entire day here so you can get a full appreciation of the variety of conditions and marine life at this fantastic dive site.

5. The Surin Islands Archipelago

The Surin Islands in the Andaman

There are a few dive sites, mainly on the southern island (Surin Tai), which are popular with a number of boats and their guides. The key to having a good dive here is to have a very knowledgeable guide to show you the highlights. Every divemaster has his or her favourite. Just jumping in and swimming around is normally disappointing for most people. The snorkelling is very nice in the protected bays, and the anchorages are wonderful. It’s right on the Burmese border, so seeing Surin gives you a taste of what the islands in the Mergui Archipelago are like.

6. South Andaman Dive Sites

Koh Ha is a small group of islands almost directly west of Koh Lana. These tiny islands, separated by channels over 50 meters deep, jut straight out of the Andaman Sea. However, unlike at Phi Phi, the water here is ordinarily quite clear, and visibility frequently exceeds 25 meters. The highlight of diving here is a series of caves or caverns on the largest of the islands, Koh Ha Yai. The caves are safe to enter, even without a light, as the entrances are large, and there is only one way in and one way out. The best part of entering these caves is that you can surface inside the island to view stalactites hanging down from the ceiling over 30 meters above the surface. The quality of light filtering through the water from the entrance is magical, and often you can see big fish swimming back and forth in front of the entrance.

The sole reason that diving has become world-class in Koh Lanta and Krabi are two pinnacles that lie approximately 25 km southwest of Koh Rok. Hin Daeng (red rock) and Hin Muang (purple rock) offers everything a diver could want, from dramatic walls and big fish action to lush tropical underwater gardens.

Leopard sharks are pretty common below the ridge on the sandy flats. Although the soft corals are not as high-profile as they are in the Similans, the colours of the corals are radically different and include shades of turquoise, yellow and blue, besides the more common pinks and purples. The colours are more pastel than the usual bold colours we commonly see in other places.

7. Hin Daeng

Hin Daeng is easily found since it protrudes about three-meters above the surface. Although not very impressive topside, underwater, the rock is huge. The southern side descends straight down to over 60m (200ft), forming the most radical vertical drop in Thailand’s seas. The wall is dotted with light growths of soft corals and a few sea fans but is otherwise devoid of life. On the eastern side, where the slope is more gentle, two long ridges descend into the blue, and if the currents are favourable, it is possible to swim along these ridges down to 40 meters or more. Here the soft coral becomes more lush and tall, and huge schools of jacks sweep past the ridge, surrounding the diver with a shimmering wall of silver. Ascending to the shallows, we see needlefish skip along the surface. Barracudas stalk their prey through the clear water. Swimming between the three large rocks that form the surface view of Hin Daeng, large schools of fusiliers dart to and fro as if they are afraid of the water surging through the channels.

Hin Daeng (Red Rock) is marked on Thai nautical charts thusly, and we do not know where the name came from, although I suppose fishermen named it because when the sun is setting, the rock does glow a reddish colour. During the day, it’s brown, but “Brown Rock” doesn’t roll off the tongue nicely in either English or Thai.

8. Hin Muang

Hin Muang, located just a few hundred meters from Hin Daeng, lies completely submerged. What surprised us the first time we explored the rock was the incredible amount of marine life that clung to the rock. It is as if the rock were located in another ocean and not just a short distance away from the relatively barren Hin Daeng. The name derives itself from the thick purple growth of soft corals that are everywhere. The rock itself is approximately 200 meters long, less than 20 meters wide, and is shaped like a loaf of bread with steep, vertical sides and a rounded top. The walls are decorated with large sea fans of red, white and orange. Clouds of glassfish or silver-sides school around the fans and rocky outcroppings. Carpets of anemones cover the shallower sections of the pinnacle.

Commonly, the water is so transparent and the sea so smooth that I can clearly see the splash of someone throwing the dregs of their coffee overboard–with puffy white tropical clouds as a backdrop–from a depth of over 45m (150ft)!

Whale sharks are one fish that we repeatedly see around these pinnacles, and for many years we have seen them on many of our trips there. Though we see whale sharks less now than we did in the 1990s, they are still around on a regular basis. Manta rays are rapidly becoming more of a common reason for diving in Hin Daeng, as the tops of the pinnacles act as cleaning stations for these giants.

Hin Muang was named when we found the dive site in about 1991 when my company started doing regular trips there. At that time, there were not many soft corals in Hin Daeng; it was mostly barren, with some large sea fans deeper on the wall. Hin Muang, on the other hand, was so full of soft corals when we found the rock that it was promptly named Purple Rock because the whole thing was completely purple!

Over the years, we’ve learned that soft corals come and go. Some years they are very lush and abundant, others less so. Hin Daeng is often just as lush as Hin Muang. This may be because of the nature of these types of soft corals, or humans and destructive fishing practices could cause it. Either way, they always seem to recover.


John Williams has written, co-authored, or contributed to four diving guides on Thailand, the Mergui Archipelago, and the Andaman Islands. These are the award-winning Lonely Planet Diving & Snorkeling series, Periplus Editions Diving Southeast Asia, Asian Diver Scuba Guides and Singapore’s Times Edition Diving Thailand. He has lived in Phuket and has dived in Thailand’s waters since 1987.

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Willy Thuan

Born in France a long long time ago, I started to travel the world early until I settled in Phuket in 1994. For the past 30 years, my passion for photography and my curiosity have taken me to every corner of Phuket, Bangkok and everywhere I could go in Thailand. My goal is to share my discoveries, photos and tips to help travellers plan their holidays by making Phuket 101 as easy as possible to use for everyone!