Twins: Koh Nang Yuan's Twin Peaks Pinnacle Dive Site

Twins is probably the busiest dive site on Koh Tao, and it earns that reputation honestly. Just off the west side of Koh Nang Yuan, it is where thousands of Open Water students do their training dives, thanks to flat conditions, almost no current and a layout you can understand in minutes. Locals also call it Twins Pinnacle or Twin Peaks, and if you are searching for the Twins dive site on Koh Tao, this is the one.

Despite the name, there are three granite formations here: two main pinnacles of boulders and a smaller, deeper cluster to the west. They sit in a rough east-to-west line on a sandy floor, so you can hardly get lost. Add hard and soft corals, ledges, cracks and a saddleback anemonefish family and you have a site that suits beginners but still holds the interest of experienced divers.

Twins dive site map

1. 1Koh Nang Yuan, to the east
2. 3Shallow peak, top 5 m
3. 4Middle peak, top 8 m
4. 5Smaller deeper peak, to 20 m
5. 6Saddleback anemone, ringed off
6. 7Buoyancy World, short swim north

Diving Twins: the route

A good plan is to begin at the smaller, deeper peak in the west, head east to the middle peak, and finish on the shallow peak. That way you spend your deepest time first, finish in the shallows and can use the top of the shallow peak for your safety stop. If you prefer, the sandy area around the rocks makes a handy spot for skills practice, which is why so many courses run here.

Because Buoyancy World lies a short swim north across the sand, it is easy to combine the two. Many groups warm up with a few skills among the sculptures and then explore the pinnacles.

Twins also pairs well with a second dive at nearby No Name Pinnacle, which lies about 200 m to the west. If you are on a course, your instructor will usually choose the order for you, but fun divers can mix and match.

Underwater layout

• Shallow peak: tops out around 5 m, with ledges and shadowed areas, and blue-spotted rays resting underneath.
• Middle peak: top around 8 m. It has an archway on its north side that some people call a swim-through, but it is only for divers confident with their buoyancy.
• Smaller deeper peak: the westernmost group, reaching about 18 to 20 m.
• Saddleback anemone: southeast of the middle peak, surrounded by a ring of rocks that you must not enter.
• Sandy seabed: white sand with a few channels, at around 16 m.
• Buoyancy World: artificial training reef a short swim to the north.

The average depth is about 10 to 12 m, and the deepest points are around 18 to 22 m depending on where you measure.

Marine life at Twins

The rocks are covered in hard and soft corals and attract a steady crowd: Weibel's butterflyfish, six-banded angelfish, wrasse, parrotfish, bannerfish, snapper and fusiliers. Moray eels watch from crevices, and yellow boxfish tuck into the cracks. The deeper peak sometimes has longface emperor, and groupers and trevally drift past.

Look closely for the small stuff: nudibranchs, pipefish, wart slugs, cowfish, scribbled filefish and various shrimp. The saddleback anemonefish family is a highlight, so watch them from outside the ring of rocks. Turtles pass occasionally, and banded sea kraits are sometimes seen.

Twins is a good site for learning to look. Slow down at each rock, check the ledges and shadows, and scan the sand for anything that does not belong. Divers who return several times often notice something new on each visit.

Conditions and best time to dive

Twins is flat almost all year, with very little current. Visibility is typically about 5 to 20 m, and up to 25 m has been reported. Because it is sheltered by Nang Yuan, it can be dived in most months, even when the weather is unsettled. The June to August monsoon can bring wind and chop at the surface, which is the main thing to watch for.

Tips from local divers

• Explore the smaller deeper peak first, then the middle peak.
• Check the cracks for pipefish and yellow boxfish.
• Look under the ledges of the shallow peak for blue-spotted rays.
• Dive early or late to avoid the peak of training traffic.
• Stay out of the ring of rocks around the anemone.

Safety notes

The main issue at Twins is crowds, with training groups sharing a small area, so keep track of your own group and your buddy. Watch your fins around other divers and the corals, and only enter the north archway on the middle peak if your buoyancy is solid. At the surface, monsoon wind and chop from June to August can make boarding and entries bumpy.

Why dive Twins

• Three granite pinnacles on white sand
• Saddleback anemonefish family
• Blue-spotted rays under the shallow peak
• Easy conditions with little current
• Next to the Buoyancy World training reef
• Often the busiest dive site on Koh Tao

Twins: frequently asked questions

Nearby dive sites

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