Similan Islands Diving: Exploring Thailand’s Best Islands
January 15, 2025
The Similan Islands, part of Thailand’s Andaman Sea, offer some of the best diving experiences in Southeast Asia. Known for their vibrant coral reefs, crystal-clear waters, and diverse marine life, these islands attract divers from around the globe. Whether you are diving alongside manta rays or exploring fascinating underwater rock formations, Similan Islands diving is an unforgettable adventure. With world-class dive sites, including drift dives, pinnacles, and reef encounters, this destination is a must for anyone passionate about underwater exploration.
Why You Should Go Diving in the Similan Islands
Similan Islands diving is a dream for both seasoned divers and beginners. The underwater landscapes are striking, with dramatic rock formations, colorful coral gardens, and an abundance of marine life. You can expect to dive through swim-throughs, encounter pelagics like manta rays and whale sharks, and explore both shallow and deep reefs.
What makes the experience even more special is the warmth of the local people. Known for being some of the kindest and most welcoming in the world, their hospitality ensures that your dive trip is memorable both in and out of the water. The marine life is equally impressive, from tiny critters like nudibranchs to large schools of fish, sea turtles, and reef sharks.
The Similan Islands are famous for their soft and hard corals, creating vibrant underwater vistas. The dive conditions are excellent, with warm water temperatures year-round, exceptional visibility, and generally mild currents, making it ideal for a range of diving experiences, from leisurely reef dives to more adventurous drift dives.
Top Highlights of Diving in the Similan Islands
The Similan Islands are renowned for offering some of the best diving in Thailand, featuring a variety of underwater environments that cater to divers of all skill levels. From thrilling drift dives to serene coral gardens, these waters are packed with marine life, making each Similan Islands diving experience unforgettable and unique.
1.Richelieu Rock
Arguably the most famous highlight of diving in Thailand, Richelieu Rock is a hotspot for large pelagics. Located north of the Similan Islands, this remote pinnacle draws in an impressive array of marine life, including whale sharks and manta rays.
Rich in both macro and wide-angle subjects, the site is covered in soft corals, with crevices hiding species like harlequin shrimp, seahorses, and octopus. Divers flock here for the chance to witness the spectacle of schooling fish, alongside the occasional appearance of pelagic giants.
2.Koh Tachai Pinnacle
Known for its strong currents and big fish action, Koh Tachai Pinnacle is one of the top sites for thrill-seekers. This open-ocean pinnacle, surrounded by huge granite boulders, draws in large schools of barracuda, trevally, and even manta rays.
It is a dynamic dive full of movement, where marine predators like groupers and tuna hunt in the currents. Advanced divers often prefer this site for its fast pace and depth, making it an exhilarating experience.
3.Koh Bon West
A favorite for manta ray encounters, Koh Bon West is renowned for its cleaning stations where these graceful rays come to rid themselves of parasites. The vertical limestone walls of the site are adorned with colorful soft corals and sea fans, creating a vibrant backdrop for both macro enthusiasts and photographers. Divers can also explore the site’s nooks and crannies, where smaller critters like shrimp and nudibranchs hide.
4.Christmas Point
This dive site, located on the northwest corner of Ko Bangu, features dramatic underwater landscapes made up of towering boulders and intriguing swim-throughs. The massive rock formations create a maze-like experience, while the surrounding coral gardens are home to a variety of reef fish.
In deeper waters, divers can often spot larger species such as trevally, groupers, and sweetlips, making Christmas Point a diverse and exciting site for underwater exploration.
5.Elephant Head Rock
Elephant Head Rock, named after its unique rock formation, is a dive site for experienced divers. This dive is a thrilling journey through underwater caverns, archways, and tunnels created by large boulders.
With strong currents and complex topography, this site attracts big species like moray eels, octopuses, and reef sharks. The swim-throughs and crevices offer exciting challenges, making it a must for divers looking for an adrenaline-pumping experience.
6.Donald Duck Bay
Named after a rock resembling the famous cartoon character, Donald Duck Bay offers a more relaxed Similan Islands diving experience, perfect for night dives. The shallow bay is full of interesting macro life, including cuttlefish, crabs, shrimp, and octopuses.
It is an ideal spot to wind down after a day of more intense dives, providing opportunities to focus on smaller marine creatures in a calm and sheltered environment.
7.Shark Fin Reef
Shark Fin Reef is a vast granite formation known for its steep drop-offs and diverse marine life. The site is a great place to spot reef sharks, rays, and large schools of fish like fusiliers and snappers.
With its sharp rock formations and strong currents, Shark Fin Reef offers a dramatic underwater topography that attracts both macro life and larger pelagics, providing a well-rounded Similan Islands diving experience.
8.West of Eden & Deep Six
These two dive sites combine to offer one of the most iconic Similan Islands diving experiences. West of Eden showcases vibrant soft corals and sea fans, while Deep Six offers deeper reefs and pinnacles, home to larger marine life like turtles, rays, and moray eels.
The variety of both macro and wide-angle subjects, along with the stunning underwater landscapes, make this a must-visit for photographers and divers alike.
9.North Point
Located at the northern end of the Similan Islands, North Point features a dramatic underwater landscape with massive granite boulders creating swim-throughs and canyons. The deeper sections of the site are home to reef sharks, rays, and even giant guitarfish, while the shallower areas host ribbon eels, mantis shrimp, and schools of reef fish.
North Point is also a great location for spotting pelagics like trevally and barracuda, and occasionally, a passing manta ray.
10.Boulder City
Boulder City is a site known for its huge underwater boulders scattered across the sandy seabed, creating a stunning backdrop for Similan Islands diving. The site’s swift currents bring in larger species like manta rays and whale sharks, while the rocks themselves are covered in colorful soft corals and sea fans.
It is a popular choice for advanced divers due to the challenging conditions and the abundance of pelagic activity that the currents attract.
Activities for Your Non-Diving Days
- Visit the stunning Surin National Park
When you are not exploring the underwater wonders of the Similan Islands, there are plenty of unique activities to experience on land. A boat trip to the Surin Islands is a must and offers the chance to go snorkeling in warm, calm waters with beautiful hard coral gardens and sea turtles. The Surin National Park is a prime spot for wildlife sightings, and its pristine beaches and snorkeling spots make for a peaceful retreat.
- Meet an indigenous sea nomad community
At the Surin Islands, you can also meet the Moken people, an indigenous sea nomad community who have lived in harmony with the ocean for centuries. The Moken’s deep cultural ties to the sea offer a glimpse into their traditional way of life, from their boat-building skills to their vast knowledge of marine ecosystems.
Visiting their village provides an authentic cultural exchange, and you will walk away with a profound appreciation for their enduring connection to the natural world.
- Explore Thailand’s rainforests and lakes
If you want to explore more of Thailand’s lush landscapes, Khao Sok National Park is another incredible destination. Known for its dramatic limestone cliffs, dense rainforests, and the striking Cheow Lan Lake, this park is perfect for adventure seekers and nature lovers alike.
You can hike through the jungle, discovering hidden waterfalls and spotting wildlife such as gibbons and hornbills. Alternatively, take a kayak out onto the tranquil lake, where the emerald waters reflect the towering limestone karsts.
For a more immersive experience, consider staying overnight on a floating raft house on the lake, where you can soak in the serene atmosphere surrounded by Thailand’s stunning natural beauty.
Whether you are trekking through the rainforest or simply relaxing on the water, Khao Sok offers a captivating way to spend your days in between exploring all that Similan Islands diving has to offer.
Best Time of Year for Similan Islands Diving
The ideal time for diving in the Similan Islands is between November and May, when the weather is dry, and the seas are calm. The official Similan Islands diving season kicks off on October 15th and runs until May 15th, with the peak months from December to April offering the best conditions.
During this period, divers can expect clear waters with visibility often reaching up to 30 meters (100 feet). If you want to see manta rays or whale sharks, February through April provides the greatest chances of spotting these majestic creatures.
Although the Similan Islands are closed from mid-May to mid-October due to the monsoon season, diving in Phuket and Phi Phi is still possible year-round. Even during the rainy season, you will experience a mix of sunny days and occasional rain, and there are still plenty of great dive sites to explore with fewer tourists.
However, for the best Similan Islands diving experience, the dry season between November and April offers the most reliable weather and underwater conditions.
Experience Level Needed
Similan Islands diving offers something for everyone, from those who have just started scuba diving to advanced divers. Many dive sites, like Donald Duck Bay and Christmas Point, are perfect for Open Water Divers due to their shallow depths and calm conditions.
However, more challenging sites, such as Koh Tachai Pinnacle and Elephant Head Rock, are better suited for intermediate and advanced divers due to stronger currents and deeper waters.
To make the most of the diverse dive conditions, consider taking an Advanced Open Water Diver course, which will prepare you for sites that require deep diving and drift diving skills.
If you are interested in the Similan Islands’ macro life, a night diving or underwater photography course could enhance your experience.
How to Get There
To reach the Similan Islands, you will first need to fly into Phuket International Airport (HKT), which is well-connected with international flights from major hubs. From Phuket, it is about a 90-minute drive to Khao Lak, the closest town to the islands.
The majority of Similan Islands liveaboards depart from Thap Lamu Pier, located just 15-20 minutes from Khao Lak. Alternatively, some liveaboard operators may depart directly from Phuket or Ranong, depending on the trip itinerary.
Are you ready to explore Thailand’s best islands?