Sail Rock is the ultimate dive site in the Gulf of Thailand and every certified diver visiting Koh Tao should experience it at least once. Rising dramatically from the open ocean between Koh Tao and Koh Phangan. This isolated pinnacle delivers an exceptional underwater world: extraordinary fish density, a legendary natural chimney, and regular whale shark encounters. At The Divers Boat, we run dedicated fun dive trips to Sail Rock from Koh Tao on our blue boat, exclusively for certified divers.

Why is Sail Rock the ultimate dive site in the Gulf of Thailand?

The answer comes down to one word: isolation. Sail Rock is a pinnacle that rises directly from the open ocean, far from any coastline. Thanks to this unique configuration, large fishing vessels cannot trawl the area. Which means marine life has developed freely for decades, largely undisturbed by human activity.

As a result, Sail Rock concentrates fish in extraordinary densities: barracuda in tight formation, giant trevallies, snappers, groupers, stingrays. And during favourable periods, the whale shark, the largest fish on the planet. Our team has experienced the incredible privilege of encountering two whale sharks simultaneously on a single dive. A moment that perfectly illustrates why this Koh Tao dive site is truly in a league of its own.

The Sail Rock chimney — a once-in-a-lifetime dive experience

Beyond the marine life, Sail Rock offers something entirely unique in the Gulf of Thailand. A natural vertical chimney that passes straight through the rock. You enter at 16 metres depth and ascend progressively to 5 metres. Surrounded by fish and bathed in light filtering down from the surface above.

Swimming through this passage is, without doubt, one of the most extraordinary underwater experiences in all of Southeast Asia, and one of the most photographed dive spots in Thailand. Furthermore, for divers who want to explore beyond the chimney. The maximum depth of the site reaches 40 metres, making Sail Rock an excellent choice for Advanced Open Water divers looking to push deeper.

Marine life at Sail Rock Koh Tao: what you’ll encounter

Sail Rock is one of the rare dive sites in the Gulf of Thailand where large pelagic encounters are a genuine possibility on every dive. In addition to the permanent residents — groupers, snappers and trumpetfish tucked into the rock’s crevices — several species gather here in impressive numbers.

What level do you need to dive Sail Rock?

The minimum certification required is Open Water (OW): the chimney between 5 and 16 metres is fully accessible to all OW certified divers, and the marine life at these depths is already outstanding. However, to explore the deeper zones — and particularly to reach the 40-metre base of the rock — an Advanced Open Water (AOW) certification is strongly recommended.

Moreover, Sail Rock is an ideal environment for specialty courses such as Deep Diver or Underwater Photography. Feel free to speak with The Divers Boat team about combining a specialty with your fun dive trip to this exceptional site.

Our advantage: staggered departures for a better Sail Rock dive

Sail Rock is a popular site — and crowds can quickly ruin the experience. At The Divers Boat, we deliberately schedule our departures at staggered times compared to other Koh Tao boats. By arriving as the other groups are leaving, we ensure fewer divers in the water, more undisturbed marine life, and an altogether better dive.

Our blue boat is exclusively dedicated to certified divers — no mixing with beginners, no compromises on exploration quality. Every diver on board holds at minimum an Open Water certification, which ensures group cohesion and allows us to make the most of every minute underwater.

Dive Sail Rock from Koh Tao or Koh Phangan with The Divers Boat

The Divers Boat organises fun dive trips to Sail Rock from Koh Tao, departing from Mae Haad — the island’s main pier. The journey takes approximately 2 hours by boat. In addition to our Koh Tao operation, we also run a dive centre in Chaloklum, on the north of Koh Phangan, with its own dedicated boat.

From Koh Phangan, Sail Rock is just 1 hour 15 minutes away — 45 minutes less than from Koh Tao — giving you significantly more time on the site and less time in transit. Furthermore, our Koh Phangan centre offers all SSI courses from Try Scuba to Divemaster, as well as regular fun dives to Sail Rock and other nearby sites in the Gulf.