Diving in the Similan Islands

Beacon Reef

Beacon Beach is a long coral reef just off Koh Similan running parallel to the island's beach. Often used as a check dive, this site has become very popular in recent years due to the sinking of a local Similans liveaboard, the Atlantis X in 2002. Up until then, the Similan Islands lacked any sort of wreck diving.

When the captain of the Atlantis X realised the boat was taking on a huge amount of water he decided his best option was to head for the safety of the beach. However, the boat ruptured on the hard coral and slowly sank.

At just 30m from the shore, it sank backwards so that now the bow lies in 16m of water, while the stern is in 30m. Bad news for the liveaboard operators but great news for wreck diving enthusiasts and those wanting to make wreck diving part of their PADI Advanced Open Water Course in Thailand!

Time has passed since then which means there is already quite a bit of coral growth on the sunken wreck but the engines and propellers are still well preserved, adding to the attraction. Batfish have moved in and serenely hang-out unperturbed as Similan divers explore the bulk of the wreck. Other fish that have made the wreck their home are several lionfish, nudibranchs, masses of juvenile fishes, and a black-blotched stingray.

After diving the Atlantis X you'll also want to explore Beacon Reef. There are more than 300 different hard coral species on the reef making it the most varied coral reef for diving in the Similan Islands. It boasts a steep drop-off reaching a depth of 35m and is home to numerous nudibranchs and scorpionfish. You can also find here the devil firefish which are often referred to as the most beautiful fish in the sea.

The unusual bigeye fish are the more mysterious inhabitants of the reef. They can change colour from a deep scarlet to bright silver right before your eyes! You can find them hiding under the coral ledges or feeding along the reef flats.

There is also plenty of white sand here making this a great site for a sunset dive. During your safety stop on the shallower part of the reef you will be accompanied by stone fishes, lobsters, sea snakes and octopus.

Beacon Reef lies to the north of Beacon Point and covers the whole eastern coast of Koh Similan (Island no. 8), the largest of the Similan Islands.

Beacon Reef Reef Basics: Wreck dive and fringing reef
Depth: 5 - 35m
Visibility: 20 - 40m
Currents: Easy
Surface conditions: Calm
Water temperature: 26 - 29°C
Experience level: Intermediate
Number of dive sites: 2
Diving season: October to May
Distance: ~90 km northwest of Phuket, 65 km west of Khao Lak
Access: Liveaboards and daytrips

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