Top Dive Sites in the Nicobar Islands: Campbell Shoal to Galathea Bay
The Nicobar Islands have exactly three named, documented dive sites in published sources — and a handful of generalized reef zones that make up the rest of the archipelago's known underwater landscape. This is not a destination with 50 sites ranked by PADI five-star reviews. It is a place where the lack of documentation is itself the defining feature.
This guide covers what is known, ranked by diving quality and ecological significance. Every site here requires expedition-level planning to reach. None have tank fills, mooring buoys, or any other dive infrastructure. That is the trade-off for diving reefs that have never been commercialized.
1. Campbell Shoal — The Seamount
Depth range: 5–40 m | Skill level: Advanced | Best months: January–April | Current: Moderate to strong
Campbell Shoal is the jewel of the Nicobar Islands. This seamount rises from 40 m nearly to the surface within Campbell Bay National Park, creating a classic seamount ecosystem. The nutrient-rich upwellings that hit the pinnacle attract a concentration of marine life that rivals better-known seamounts like South Africa's Protea Banks or Indonesia's Komodo seamounts.
What you will see: Reef sharks (grey reef and whitetip are common), schooling jacks in dense aggregations, large barracuda, giant grouper, and manta rays that visit the cleaning stations on the pinnacle during the northeast monsoon. The hard coral cover on the upper slope is excellent — healthy Acropora tables and massive Porites formations dominate the reefscape.
The dive experience: The seamount creates its own current patterns. On a typical day, you drop onto the pinnacle at 15–18 m and let the current carry you across the coral-covered slope. The reef falls away to 40+ m on the deep side, and the blue water visibility often reaches 25–30 m during peak season. Strong upwelling days can bring cooler water (25–26 °C at depth) but also the best pelagic action.
Why it ranks #1: Campbell Shoal is the only documented seamount in the Nicobar chain. Its combination of healthy reef structure, predictable upwelling, and reliable large-animal encounters makes it the single best dive in the archipelago. The SSI dive guide rates it 4.9 out of 5.0 — higher than any other documented site in the Andaman and Nicobar region.
Logistics note: This is a boat-only site. Access requires a boat from Campbell Bay settlement (30–45 minutes depending on conditions). No mooring buoys exist — expect a live-boat drift or a reef-hook hold.
2. Galathea Bay Coral Reefs — Turtle Highway
Depth range: 2–25 m | Skill level: Beginner–Intermediate | Best months: December–April | Current: Mild to moderate
Galathea Bay, on Great Nicobar's southern coast, is one of the most important sea turtle nesting sites in the Indian Ocean. The beach hosts leatherback turtles (critically endangered, up to 700 kg) from December to April, alongside hawksbill and green turtles that nest and forage year-round. The underwater environment matches the terrestrial significance.
What you will see: Sea turtles — leatherback, hawksbill, and green — are the headline species. The seagrass beds adjacent to the nesting beach are feeding grounds for post-nesting turtles and occasional dugongs. Stingrays, reef fish, and smaller reef sharks patrol the fringing reef. The mangrove channels that feed into the bay add a distinct habitat layer with juvenile fish and crustaceans.
The dive experience: This is the most versatile site in the Nicobars. The shallow seagrass beds (2–8 m) are ideal for extended bottom times and turtle observation. The fringing reef drops to 15–25 m and offers classic Indo-Pacific reef diving with good hard coral cover. Shore entry is possible at high tide from the beach. The bay geography provides shelter from most wind directions.
Why it ranks #2: The combination of critically endangered turtle species, excellent fringing reef, and the Galathea Bay National Park protection makes this the most ecologically significant site in the archipelago. The chance to see a 700 kg leatherback turtle underwater is a bucket-list experience.
3. Indira Point Reefs — Channel Convergence
Depth range: 3–30 m | Skill level: Advanced | Best months: January–April | Current: Moderate to strong
Indira Point is the southernmost point of India — and the reef here sits at the convergence of the Bay of Bengal and the Andaman Sea, funneled through the Six Degree Channel. This mixing-zone ecology is unique. The 2004 tsunami caused 4.25 m of subsidence here, permanently altering the reef structure. The result is a living laboratory of coral recovery with unusual topography.
What you will see: Large pelagics dominate — tuna, barracuda, mackerel, and trevally hunt the channel waters. Reef sharks are common. Manta rays appear seasonally at cleaning stations. The coral recovery is remarkable — new Acropora growth on the subsided reef matrix has created an intricate three-dimensional habitat that attracts high fish density.
The dive experience: This is a current dive. The Six Degree Channel funnels tidal flow between Great Nicobar and Sumatra, and the current at Indira Point can run strong (2+ knots on spring tides). The drop-off structure means you descend from shallow reef into deep blue water rapidly — there is a literal edge where the reef shelf ends and the channel bottom drops beyond recreational limits.
Why it ranks #3: The convergence-zone ecology and the post-tsunami coral recovery story make this site scientifically unique. No other Indian dive site offers this combination of geography, history, and underwater regeneration.
4. Car Nicobar Fringing Reefs — Dugong Country
Depth range: 2–20 m | Skill level: Beginner–Intermediate | Best months: November–May | Current: Mild
The northernmost inhabited island of the Nicobar chain, Car Nicobar is home to extensive seagrass meadows that support one of India's last viable dugong populations. The fringing reefs along the western and southern coasts are protected by the island's geography, creating the calmest diving conditions in the archipelago.
What you will see: Dugongs are the signature species here — these gentle "sea cows" graze the seagrass meadows in the shallow bays. Hard and soft coral cover is good on the reef slopes. Reef sharks, turtles, stingrays, and a high diversity of reef fish (parrotfish, angelfish, butterflyfish, grouper) are consistently present. The calm conditions make this the best site for less experienced expedition team members.
The dive experience: Diveable from shore or by small boat from Car Nicobar's jetty. The shallow profile (2–15 m typical) allows extended dive times. The seagrass beds are best explored at high tide when dugongs come closer to shore to feed. The reef patches are scattered — this is not one continuous wall but a mosaic of coral bommies, sandy patches, and seagrass.
Why it ranks #4: Car Nicobar is the most accessible diveable island in the group (relative to the rest of the Nicobars), and the dugong habitat alone makes it a high-priority destination for any expedition.
5. Tillangchong Reefs — Zero Human Footprint
Depth range: 3–22 m | Skill level: Intermediate | Best months: January–April, October–November | Current: Mild to moderate
Tillangchong is a completely uninhabited wildlife sanctuary. No people live here. No structures exist. Seabird colonies nest on the cliffs, turtles lay eggs on the beaches, and the surrounding fringing reefs have seen essentially zero human impact. This is expedition diving's gold standard.
What you will see: Pristine fringing reef with high coral cover and abundant fish life. Reef sharks are common and unafraid. The absence of fishing pressure means grouper and snapper reach sizes rarely seen elsewhere. Seabird colonies above translate to nutrient input below — the reef benefits from the guano fertilization, creating unusually lush coral growth.
The dive experience: Access is the challenge. Tillangchong requires a dedicated boat trip from Car Nicobar or the central islands. There is no jetty, no anchorage — you anchor on the reef shelf or drift. The reward is the sense of discovery. Everything you see here is in its natural state, unchanged by human activity.
Why it ranks #5: For divers who value pristine wilderness over creature comforts, Tillangchong may be the most rewarding site in the Nicobars. The complete absence of human presence is increasingly rare.
6. Nancowry-Kamorta Channel Reefs — Deep Harbour
Depth range: 3–30 m | Skill level: Advanced | Best months: December–April | Current: Moderate to strong
The deep-water natural harbour between Nancowry and Kamorta islands in the central Nicobar group creates a unique channel environment. Nutrient-rich mixing zones between the two islands attract pelagic species, and the channel's depth creates dramatic wall features.
What you will see: Tuna and barracuda patrol the channel. Reef sharks are common on the channel slopes. Rays, including the occasional manta, pass through. The wall features are among the most dramatic in the Nicobars — sheer faces dropping into the channel.
The dive experience: Current-driven diving along the channel walls. The flow varies with tidal stage — the best diving is on the slack tide when visibility peaks and current is manageable. This is not a site for photographers who want to hover in one spot; it demands comfort with drift diving.
Why it ranks #6: The wall diving here is unique in the Nicobars. Historical notes mention possible WWII remnants in the area, adding interest for wreck and history enthusiasts.
7. Katchal Island Reefs — Recovery Lab
Depth range: 2–18 m | Skill level: Beginner–Intermediate | Best months: December–April | Current: Mild
Katchal was one of the islands most dramatically reshaped by the 2004 tsunami. The island itself was permanently altered, and the surrounding reefs experienced significant damage. The coral recovery since then has been remarkable, creating an open-air laboratory of reef regeneration.
What you will see: Recovering coral communities — comparing damaged vs. regrown areas, the reef tells a story of resilience. Seagrass meadows support dugongs (second only to Car Nicobar in sighting reliability). Reef fish are abundant. The shallow, gentle conditions make this a forgiving dive.
The dive experience: Shallow and gentle. This is an easy, long-bottom-time dive suited for all levels. The coral recovery narrative gives the dive meaning beyond the immediate visual experience.
Why it ranks #7: The post-tsunami ecology is scientifically interesting and visually unique. For divers interested in coral resilience, Katchal offers a perspective no other site in the Nicobars provides.
8. Little Nicobar Coral Reefs — Least Explored
Depth range: 2–25 m | Skill level: Advanced | Best months: December–April | Current: Moderate
Little Nicobar is, by some measures, the least-explored major reef system in India. The island is rugged and remote, with no settlements on most of its coastline. The fringing and patch reefs that encircle it have seen very few divers — possibly fewer than 100 in recorded history.
What you will see: High biodiversity in a near-pristine state. Reef sharks, large grouper, and snapper that have never known a spear gun. The coral cover is exceptional. This is as close as you can get to seeing what the Indian Ocean looked like before industrial fishing.
The dive experience: Challenging access. Little Nicobar requires a long boat trip from Campbell Bay or Car Nicobar. The exposed western coast can be rough. The eastern side is more sheltered but requires careful navigation.
Why it ranks #8: The "least explored" status is the attraction. For expedition divers who want to see a reef that has barely been touched, Little Nicobar delivers.
9. Campbell Bay Fringing Reefs — The Basecamp Dives
Depth range: 2–20 m | Skill level: Beginner | Best months: November–May | Current: Mild
These are the fringing reef patches along the northern coast of Great Nicobar, directly accessible from the Campbell Bay settlement. Multiple small reef patches and coral gardens are scattered along the coast. This is where expedition teams do their check-out dives and shallow reef exploration.
What you will see: Parrotfish, angelfish, butterflyfish, snapper, and grouper populate the coral gardens. Turtles, reef sharks, octopus, and moray eels are frequently encountered. The diversity is high even if the individual site features are not dramatic.
The dive experience: Shore-diveable from Campbell Bay at high tide. Shallow, low-current, forgiving conditions make this the ideal site for equipment checks, buoyancy refreshers, and relaxed photography dives. Multiple patches mean you can dive a different spot each day.
Why it ranks #9: It is the only site in the Nicobars with practical shore access from the only settlement. Every expedition starts and ends here. It is the basecamp reef — and basecamp reefs have their own value.