Red Rock Koh Tao Dive Site: Depth, Swim-Through & Level

Featured image: kallerna, CC BY-SA 4.0, via Wikimedia Commons.

Red Rock Koh Tao at a glance

Funky Turtle describes Red Rock as an underwater rock about 50 m (164 ft) from the island shoreline. It is also called Nangyuan Pinnacle. The top sits 2–4 m (7–13 ft) below the surface, and a descent reaches 18–20+ m (59–66 ft). Most Red Rock detail comes from that one operator, so ask your own dive shop for its briefing before you commit.

• Location: northeast side of Koh Nang Yuan, also called Nangyuan Pinnacle.
• Depth: top at 2–4 m (7–13 ft), base at 18–20+ m (59–66 ft).
• Level: certified divers and Advanced Open Water trainees, per Funky Turtle.
• Key features: a small pinnacle, overhangs, small crevices and a short swim-through cave.
• Cave entrance: around 11–12 m (36–39 ft).
• Gear note: bring a torch for the crevices and the cave.

Is Red Rock right for your level?

Red Rock suits divers who hold steady buoyancy at 12–18 m (39–59 ft). Funky Turtle places it at certified level, with Advanced Open Water trainees included. Read PADI's Advanced Open Water course outline if you are unsure where you sit. Overhangs and crevices reward slow finning and punish dangling gauges. Divers still learning to hover should start somewhere more forgiving, such as Twins or Buoyancy World.

• Choose Red Rock if you can hover without touching rock, carry a torch and track your gas.
• Choose another site if you are new to Open Water diving and still correcting your depth.
• Choose another site if overhangs or a confined swim-through make you tense.
• Choose another site if you have no torch and your shop cannot lend one.

What the dive looks like

Expect the dive to follow the shape of the rock. You drop down the pinnacle toward the 18–20+ m (59–66 ft) base, then work back up past overhangs and crevices. Because Red Rock is small, you can circle it slowly instead of covering distance. Once you have seen the high point, Funky Turtle says divers can head west along the Koh Nang Yuan shoreline. Corals line that edge, and the same operator mentions turtles and schools of trevally and snapper. Your guide sets the actual route on the day, so treat this as a typical profile, not a fixed plan.

• Descent: down the pinnacle toward the base at 18–20+ m (59–66 ft).
• Middle: overhangs and small crevices; use your torch.
• Cave: a short swim-through with an entrance at roughly 11–12 m (36–39 ft).
• Return: west along the shoreline, shallower and gentler.

Marine life to expect

Funky Turtle lists a broad range of species at Red Rock, though sightings are never guaranteed. Reef fish gather around the rock, while the crevices and cave hold smaller creatures. The shoreline run adds trevally and possibly turtles. Plan on a good dive, not on a particular animal.

• Reef fish: butterflyfish, angelfish, longfin bannerfish, anemonefish, red-breasted wrasse and parrotfish.
• Rock and cave dwellers: cleaner shrimp, wart slugs and pipefish.
• Larger animals: blue-spotted stingray, sea turtles, schools of trevally and sea snakes.
• Fish with attitude: titan triggerfish are listed, so keep your distance from any nest.

Combining Red Rock with Japanese Gardens

Funky Turtle notes that divers can continue from Red Rock to Japanese Gardens on the same dive if air allows. Japanese Gardens lies east of Koh Nang Yuan and runs 6–16 m (20–52 ft), according to Impian Divers. Read our Japanese Gardens dive guide for the site itself. The combination gives two sites for one tank, but only for divers with good gas management. If you have used a lot of air on the pinnacle, stay put and finish along the shoreline.

• Agree a turn pressure with your guide before you descend.
• Spend less time at 18–20 m (59–66 ft) if you plan to continue.
• Ask your guide whether current makes the transfer sensible that day.
• Skip the transfer if your gas reserve is below your usual ascent margin.

Red Rock vs nearby Nang Yuan sites

Three other Nang Yuan sites make useful comparisons. Twins is a shallow, sandy training site, and Japanese Gardens is gentle and sandy. Green Rock is the closest match for swim-throughs. Depths below come from Black Turtle Dive and Impian Divers. Red Rock figures come from Funky Turtle.

Getting there and booking

Red Rock is off Koh Nang Yuan, so you reach it by dive boat from Koh Tao. Impian Divers says Koh Tao has at least 20 sites within 20 to 40 minutes by boat. That operator runs morning trips to deeper sites and afternoon trips to shallower spots around Nang Yuan. Your shop picks the itinerary on the day from weather and group level. When booking a fun dive, ask whether Red Rock is on the schedule and what certification the guide expects. Impian Divers lists groups of up to 4 divers per instructor, which is a fair benchmark to ask for. Fees for fun dives, gear and the Nang Yuan visit differ by shop, so ask for the inclusions in writing.

Seasons, visibility and safety

Dive-travel operators generally put the best Koh Tao conditions between March and September. July and August are the busiest months. October and November can bring reduced visibility and more swell, and today is 12 November 2026, so expect variable days. Carry a torch, plan gas with a reserve, and stay off the rock near overhangs. Dive with a licensed operator and follow the briefing. The Divers Alert Network publishes dive-safety and insurance guidance worth reading before a trip. Marine park rules around Koh Nang Yuan can change, so ask your shop what applies on your day.

• Common mistake: leaving the torch on the boat.
• Common mistake: drifting into overhangs with poor buoyancy.
• Common mistake: rushing the swim-through.
• Common mistake: burning gas on the pinnacle and missing the shoreline.
• Common mistake: assuming turtles or sea snakes are guaranteed.

Other Koh Tao dive sites to plan next

After Red Rock, step up or down by level. For deeper offshore trips, look at Chumphon Pinnacle, Koh Tao: Depth, Wildlife & Who It Suits and the Southwest Pinnacle Koh Tao Dive Site: What to Know pinnacles. Wreck fans can read about HTMS Sattakut Wreck Dive Koh Tao: Depth, Level & Tips, which Black Turtle Dive places 20 minutes from the main pier. Advanced divers can add No Name Pinnacle, Koh Tao: Depth, Cert Level and Is It Worth It?. For easier days, try White Rock or Shark Island. Sail Rock, Koh Tao: Dive Guide, Logistics, Who It Suits is a longer outing from the same hub.