Red Rock Koh Nang Yuan's Pinnacle Dive Site

Red Rock is a granite pinnacle sitting about 50 m off the east coast of Koh Nang Yuan, on the side facing Koh Tao. It rises from around 20 m of water to within a few metres of the surface, and it is also known as Nang Yuan Pinnacle. What makes it a good all-rounder is that it packs a pinnacle, a cave and an easy coastal drift into a single dive.

Open Water divers can dive it, and the deeper eastern side suits anyone who wants a bit more depth. The cave needs reasonable buoyancy, and the swim to it crosses open sand, so a compass is useful. Most dives end at Japanese Gardens, which gives you a shallow, relaxed finish.

Red Rock dive site map

1. 1Koh Nang Yuan, east coast
2. 2Red Rock pinnacle, top 3 m
3. 3Nang Yuan cave, boulder archways
4. 4Sand gap, about 18 m
5. 5Coastline reef to Japanese Gardens, 12 to 15 m
6. 6North coast rocks, 8 to 10 m

Diving Red Rock: the route

You descend onto the pinnacle and circle it, keeping the large crack that runs around the rock on your side. The deeper east and north faces are where most of the life is, so take your time there. Once you have done a lap, a short compass heading west across a sandy gap takes you to the Nang Yuan cave.

From the cave you can go north along the coast or south along the reef. The south option is the classic one: the shoreline reef runs at around 12 to 15 m and gradually shallows into the coral bay of Japanese Gardens, where you can spend your safety stop among the bommies.

The dive suits fun divers, refreshers and anyone practising navigation, since the compass swim to the cave is a natural exercise. It is also a good site for photography: the crack gives you plenty of close subjects, and the light filtering into the cave is worth a few frames. Plan your gas for the pinnacle first, because the deeper faces are where you will want to linger.

Underwater layout

• The pinnacle: a single granite rock with its top about 3 m below the surface, standing on sand at roughly 18 to 22 m on the deeper sides.
• The crack: a deep fissure around the rock that shelters a lot of the marine life.
• Sand gap: a short open stretch between the pinnacle and the island, about a compass-bearing swim.
• Nang Yuan cave: boulders piled into archways along the coast, forming a long swim-through lit from above.
• Coastline reef: runs south at 12 to 15 m towards Japanese Gardens.
• North coast rocks: small rocks at around 8 to 10 m.

The rock tops and the sand floor are only about 15 to 20 m apart, so the whole pinnacle is easy to read once you are down. The Nang Yuan coast lies to the west and Koh Tao to the east, which helps if you lose your bearings.

Marine life at Red Rock

The crack is the place to look. Moray eels, large groupers, pufferfish, yellow boxfish and scorpionfish sit in the gaps, and harlequin sweetlips, titan and yellowmargin triggerfish, bannerfish, angelfish and parrotfish cruise around the rock. Schools of yellowtail barracuda and trevally pass by, and snapper hang over the sand.

For close-up work, look for wart slugs, Durban dancing shrimp, glass cleaner shrimp and pipefish. On the cave floor, blue-spotted ribbontail rays and Jenkins whiprays often rest in the sand. Turtles and banded sea snakes are regular visitors, and pink-tailed triggerfish have been reported along the north coast at 8 to 10 m.

Because the pinnacle rises on its own from the sand, the deeper faces reward a slow lap: look into every part of the crack rather than swimming past it.

Conditions and best time to dive

Current is usually gentle but can pick up around the full moon. Visibility is typically about 10 m and can reach 20 m or more on a clear day. The calmest, clearest conditions come in the dry-season months, while June to August and mid-November to early January tend to be the least reliable.

Tips from local divers

• Bring a torch to light up the cracks and the cave ceiling.
• Practise your compass heading beforehand. The swim from the pinnacle to the cave crosses open sand.
• Spend extra time on the deeper eastern and northern faces, where most of the life lives.
• Check the tide and moon phase, because current can build around full moon.
• Finish at Japanese Gardens for a shallow, easy safety stop.

Safety notes

The deep side reaches about 22 m, so keep an eye on your depth and gas if you linger there. Current is stronger around the full moon, and the cave swim-through asks for neutral buoyancy: keep your fins off the bottom and your distance from the diver ahead.

Why dive Red Rock

• Granite pinnacle with a crack full of morays and shrimp
• Nang Yuan cave swim-through under boulder archways
• Easy drift finish into Japanese Gardens
• Blue-spotted ribbontail rays and Jenkins whiprays in the cave
• Green and hawksbill turtles feed nearby
• Pink-tailed triggerfish reported along the north coast

Red Rock: frequently asked questions

Nearby dive sites

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