Today, piles of curious stones, some of them as big as houses, lie as though collected and later abandoned in careless heaps by some ancient race of beachcombing giants. Even Sailing Boat Rock, the distinctive formation teetering high above the cove on Koh Similan (Island No.8), has been shaped in this way.

Boulders just like these spill in jumbled piles down beneath the surface of the sea to 35 meters and beyond, where submarine peaks, canyons, caves and passageways provide scuba divers with some of the most interesting submarine prospects in the world. On the west side of the islands, currents have kept the formations clear of sand; on the coral-covered sandy slopes of the east side, the boulders have been largely buried.

Sailing cruises

The Similan Islands are best known as a diving and snorkelling destination, but the Similans' scenic moorings have also become popular with the sailing fraternity. Every year, many yachts come to cruise the Similans during the northeast monsoon (November–May, with December–February being the peak of the high season). Many are drawn by the lovely anchorages, the beaches and forests, the clear waters, and teeming marine life.

You can book bareboat sailing charters and sailing-diving cruises from Phuket. If you're on a yacht that doesn't have scuba gear or a compressor, you can always hire what you need from the dive boats that regularly come out from Phuket. Aside from sailing and diving, more and more dayboats are coming out from Phuket and Phang Nga during the high season, bringing with them crowds of sightseers, picnickers, and snorkellers.