Similan Islands diving

Mu Ko Similan national marine park

The Similan Islands diving is regarded as Thailand’s best and the Similan Islands is often referred to as one of the world’s top ten dive destinations. The marine park is made up of nine granite boulder islands that lie in a north to south line about 100 km north west of Phuket. Koh Bon and Koh Tachai are two separate islands which are also considered to be part of the Similan Islands marine park.

Similan Islands diving season

Similan Islands diving is from mid October to mid May each year. The marine park is officially closed from mid May to mid October. The ideal time of year to visit is February to April when the sea is glass flat and more pelagic fish are seen.

How to dive the Similan Islands

You can dive the Similan Islands by day trip from Phuket or Khao Lak, or by liveaboard. Liveaboards are ideal given the size of the area, the variety of dive sites, and the distance from the mainland.

A typical Similan liveaboard itinerary is 4 days 4 nights and also includes Koh Bon, Koh Tachai and Richelieu Rock.

If you don’t mind longish transfers then Similan diving day trips with 2 dives run five days per week from Phuket.

What is Similan Islands diving like?

Similan islands diving is very different on the east and west  coasts. This variety is quite unique.

The east coast dive sites have gently sloping coral reefs, with gardens of hard and soft corals, starting shallow and sloping down to the white sandy bottom at 30-40 m. Massive coral bommies, completely covered with soft corals, sponges and sea fans rise from the sea bed. The schools of tropical fish are almost overwhelming in number (the fish in the Similan islands are that bit bigger than at any other Thailand dive site).

The east coast reefs are relatively easy dives with gentle currents and very clear water.

West coast dive sites, as well as the north and south tips of the islands, offer a different type of diving which is more challenging. Currents can be strong so they are not always suitable for inexperienced divers.

Huge granite boulders form stunning seascapes with swim-thrus, tunnels and caverns. Giant gorgonian seafans grip to the edge of the boulders, feeding off the currents that swirl around the rocks. Soft corals grow around the boulders. Pelagic fish like the currents at these dive sites., mantas and eagle rays are often seen. In the deeper areas you can also see reef sharks and leopard sharks.

Similan Islands beaches

The Similan Islands also has some of Thailand’s best beaches with the whitest sand. You will not have time to visit the beach on a day trip but liveaboards include beach and island excursions. There are some short jungle trails and some fabulous viewpoints.