The Similan Islands are an archipelago consisting of eleven islands located just 50 km off the west coast of Thailand. They have been protected and managed as the Similan National Park since 1982, and are planned to be listed as a UNESCO World Heritage Site soon. Most liveaboards do 4 or 5 day trips out to these islands, with departure from either Thap Lamu Pier nearby Khao Lak, or Chalong Pier in southern Phuket. All trips offer guests free transfers from anywhere in Phuket, and most places in Khao Lak before and after the cruise.
The diving in the Similan Islands is primarily done on and around massive stacks of boulders, which have plenty of overhangs and swim through spaces to explore. Some dive sites are also simply sloping reefs that can be drifted if there is current, and a few are completely submerged sea mounds. These sites offer divers a chance to dive in calm comfortable conditions, with warm water and good visibility the majority of the diving season. The dive sites are accessible for all levels of divers, and groups are limited to only 4 guests to 1 dive guide.
Recently the islands oh Koh Bon and Koh Tachai have also been included into the park's jurisdiction. These two islands have sites which are real highlights in the Similan Islands. Koh Bon gives divers the best opportunity to see majestic manta rays up close and personal. While Koh Tachai has a stunning sea mound dive covered in beautiful corals, where you can sometimes find sleeping leopard sharks or a passing whale shark.
One of the best known dive sites in the world, Richelieu Rock, is also dived on all liveaboards to the islands. This site is considered by many as a top ten world wide, and is completely covered in soft corals, large sea fans, and with huge schools of snappers and barracudas hanging just nearby the reef. The site is a submerged pinnacle which breaks the surface only during low tide. It drops quickly to between 20 and 30 meters to a sandy bottom with several coral outcrops. This is the most common place to encounter whale sharks in the entire region, and is by far the most colourful and vibrant site in Thailand.