Just off the coast of Phang Nga in the midst of the sparkling Andaman Sea, the world-famous Similan Islands, and the lesser-known but equally spectacular Surin Islands, attract divers the world over to their warm, turquoise waters. The marine life around these islands is rich and diverse, showcasing the full catalog of Southeast Asian species amongst healthy reefs of colorful coral. Both island chains enjoy protected status as Thai National Parks, a testament to their important and valuable role in Thailand’s natural heritage.

The Similan Islands

The Similan Islands is an archipelago of nine islands lying north to south only 50km from the Thai coastline. Protected within the Similan Islands National Park, an area of approximately 140 square kilometers also includes the two northern outcrops of Ko Bon and Ko Tachai. While the islands do have individual names, they are more commonly known by their numbers one through nine.

It’s hard to believe that only five years ago the Similan Islands were a far cry from the tropical paradise as they appear today. Their popularity eventually became their downfall as close to 1 million visitors descended on the islands each year to experience their beauty for themselves. Delicate habitats were unable to cope with the sheer number of tourists, and degradation of the islands’ vegetation and damage to corals was inevitable. Environmental factors caused an additional blow to the area’s marine life in 2010, with a global warming phenomenon called the Reverse Indian Ocean Dipole causing widespread coral bleaching damage to 90% of corals.

Drastic action followed, and in October 2016 the Similan Islands National Park was closed to visitors and almost all tourist accommodation on the islands removed. After two years of recovery, the park reopened in 2018, but with a closely regulated cap on visitor numbers. Of the nine islands in the chain, access to three is now restricted to protect nesting turtles, and one is privately owned. A limit of 3,325 visitors per day during the open season of mid-October to mid-May ensures minimal impact from tourism and protects the islands to be appreciated as they should, in all their uncrowded natural beauty. Previously removed accommodations have not been replaced, and now the best way to visit these beautiful islands is by day trip boat or dive liveaboard.

Entrance Fees - Foreign visitors can expect to pay 500 Baht to enter the national park while local tourists pay 50 Baht. There is also a 200 baht per day dive fee.

The Surin Islands

One hundred kilometers north of the Similan Islands, the five small islands that make up the Surin Islands National Park are a quieter alternative to the popular southern reaches. Only 55 kilometers from shore, and enticingly close to the Myanmar border, these exotic outcrops include the famous Richelieu Rock, supposedly named by Jaques Cousteau as one of the best dive sites in the world.

Covering an area of 135 square kilometers, the main islands in the national park are Ko Surin Nuea and Ko Surin Tai, barely separated by a narrow channel that makes for perfect snorkeling. Along with the three smaller islands, they make up one of the last untouched areas of Thailand. Although less frequently visited than the Similan Islands, the Surin Islands can become busy during the peak tourist season, with as many as 800 visitors each day.

Entrance Fees - Foreign visitors can expect to pay 500 Baht entry to the national park while local tourists pay 100 Baht.

What is there to see and do?

The region’s wildlife has made a great recovery over the last few years, and in 2019 park authorities declared the corals in both national parks ‘fully recovered’. Both island chains boast white sandy beaches that will take your breath away, and most visitors spend time relaxing or swimming in the enticingly warm water. There are many nature trails throughout the interior of the Similan Islands, however, access around the Surin Islands is far more restricted. Wildlife enthusiasts will enjoy spotting migratory birds not found elsewhere in Thailand, with a chance of sighting critically endangered species such as the streaked shearwater and Swinhoe’s storm petrel.

But without a doubt, the islands’ biggest draw is their fantastic marine life, with a huge diversity of sea creatures drawing divers and snorkelers from around the world. A fascinating underwater topography of granite boulders and impressive rock formations sets a dramatic backdrop to gently sloping reefs festooned in beautiful corals. Nutrient-rich currents sweep life-sustaining waters through the channels between islands, nourishing massive sponges and gorgonians, and attracting large filter feeds such as manta rays and whales sharks close to shore.

In and around the coral heads, thousands of reef fish create a wall of color and movement while angelfish and butterflyfish shoal above. There are several shark species to be encountered in the tropical waters including blacktip and whitetip reef sharks, zebra sharks, and leopard sharks. The Similan islands are an important nesting site for leatherback and olive ridley turtles, and these two species, along with green and hawksbill turtles are often spotted during dives. Add to all this rays, Napoleon wrasse, and large schools of pelagics such as barracuda and trevally, and every dive is a dazzling experience.

How to get there

The only way to reach the Similan and Surin Islands is by boat, and for day-trippers, there are numerous options.

From Phuket - Phuket International Airport (HKT) is the closest airport to fly into from other parts of Thailand or Southeast Asia. There are daily flights from Bangkok at reasonable return rates. Boats depart numerous times a day from nearby Chalong and Patong, and the journey to the Similan Islands takes between 2 and 4 hours depending on which island you are visiting. Although it is possible to day trip from Phuket to the Surin Islands, there are much quicker options.

From Khao Lak and Ranong to Similan Islands - Thap Lamu near Khao Lak, and Ranong further north, are the closest mainland settlements to Koh Similan (the biggest island). Boats depart regularly, and the journey takes around 2 hours. Visitors normally arrive in Khao Lak or Ranong by bus; a 90-minute journey from Phuket or 10 to 12 hours from Bangkok.

From Khao Lak and Khura Buri to Surin Islands - Khura Buri pier is the closest departure point for Surin Islands, and Thap Lamu near Khao Lak is also reasonably close. Khura Buri is a stop on the Bangkok to Phuket bus route.

A second option, and the ideal choice for divers, is to visit the islands on a liveaboard. These all-inclusive yachts generally offer 4 or 7-night trips, taking in the best sites around the island chain. Most boats will run 4 dives a day, including one dusk or night dive. There is also the option to snorkel between dives, and the possibility of a land-based excursion to explore the top-side wildlife. Some trips will include both the Similan and Surin Islands, and most depart from Khao Lak, Ranong, or Phuket.

Where to stay

There is very limited accommodation available on three of the Similan Islands, and National Park restrictions mean facilities basic, all be it clean. Koh Meang offers different types of bungalow, some with AC, for between 1,000 and 2,000 Bath p.n. Each bungalow sleeps 2 and there are 35 in total, so be sure to book well in advance. For a budget alternative, Koh Similan, Koh Meang, and Koh Tachai also have campsites with pitched tents that sleep 2 or 3 for around 500 Bath p.p.p.n.

On the Surin Islands accommodation is even more limited. There are three bungalows on Surin Nuea that sleep 4 people at a rate of 3,000 Baht p.n. Alternatively, two campsites also on Surin Nuea offer 70 pitched tents in a range of sizes at rates between 300 and 450 Baht p.n.