India's Island Territories — Andaman & Nicobar and Lakshadweep
Overview
India's two island territories — the Andaman & Nicobar Islands in the Bay of Bengal and Lakshadweep in the Arabian Sea — are geographically remote but strategically indispensable. They extend India's maritime reach, guard critical sea lanes, host unique ecosystems and tribal communities, and are among the most vulnerable to climate change and sea-level rise.
For UPSC, island territories are tested on physical geography, tribal communities, ecological significance, strategic importance, and emerging development controversies — particularly the Great Nicobar Island Development Project (2022–ongoing).
Key Fact: Andaman & Nicobar has 572 islands (only 38 permanently inhabited); Lakshadweep has 36 islands (only 11 inhabited). The Andaman Islands host South Asia's only active volcano (Barren Island). Lakshadweep is India's smallest Union Territory (32.62 km²).
Andaman & Nicobar Islands
Physical Overview
| Feature | Data |
|---|---|
| Total islands | 572 (including islets and rocks) |
| Permanently inhabited | 38 islands |
| Area | ~8,249 km² |
| Capital | Port Blair (South Andaman) |
| UT status | Since 1956 |
| Location | Bay of Bengal; 150 km south of Myanmar; 1,255 km from Chennai |
Island Groups
The archipelago is divided into two principal groups separated by the Ten Degree Channel:
| Group | Location | Key Islands |
|---|---|---|
| Andaman Group | North of 10°N | North Andaman, Middle Andaman, South Andaman, Little Andaman, Ritchie's Archipelago |
| Nicobar Group | South of 10°N | Car Nicobar, Nancowry, Great Nicobar |
| Channel | Between | Significance |
|---|---|---|
| Ten Degree Channel | Andaman (Little Andaman) and Nicobar (Car Nicobar) | Separates the two island groups; 10°N latitude |
| Duncan Passage | South Andaman and Little Andaman | ~48 km wide |
| Six Degree Channel | Great Nicobar and Sumatra (Indonesia) | Southern limit of India; connects Bay of Bengal and Andaman Sea |
Key Islands
North Andaman:
- Northernmost point: Landfall Island — northernmost point of A&N Islands
- Saddle Peak (732 m): Highest point in A&N Islands; North Andaman island
South Andaman:
- Port Blair: Administrative capital; Cellular Jail (built 1896–1906; Kala Pani; National Memorial)
- Ross Island: Former British administrative headquarters; now Netaji Subhash Chandra Bose Island (renamed 2018)
Barren Island:
- Only active volcano in South Asia — caldera type
- Located in Andaman Sea, 135 km northeast of Port Blair
- Eruptions: 1787 (recorded first), 1991 (active phase resumed), 2017–2020 (most recent sustained activity)
- Uninhabited; restricted access
Narcondam Island:
- Dormant volcano; 8 km²; ~700 m high
- Home of the Narcondam Hornbill (Rhyticeros narcondami) — Critically Endangered endemic species; found nowhere else on Earth
- Protected as Wildlife Sanctuary
Little Andaman:
- Home of the Onge tribe (PVTG)
- Coconut groves and the White Surf Waterfall
Great Nicobar Island:
- India's southernmost point: Indira Point (6°45'N) — the southernmost tip of India
- Note: Indira Point was inundated by 2004 tsunami — the lighthouse partially submerged
- Galathea Bay: On the eastern coast; site of proposed major port
- Home of the Shompen tribe (PVTG)
- Campbell Bay: Only settlement; INS Baaz — India's southernmost naval base
Volcanic Geography
| Island | Type | Status |
|---|---|---|
| Barren Island | Stratovolcano / Caldera | Active — only active volcano in South Asia |
| Narcondam | Extinct/dormant | Dormant |
Both are part of the Andaman-Sumatra volcanic arc — an extension of the Sunda Arc tectonic system. They confirm that A&N Islands are the submerged peaks of a submarine mountain range — geologically part of the Burmese arc, NOT the Indian plate.
2004 Indian Ocean Tsunami
- A&N Islands were among the most severely affected regions
- Indira Point (Great Nicobar): Lighthouse and surrounding land subsided ~4 m; the point is now partially submerged
- ~3,500 deaths in A&N Islands alone
- Changed the strategic calculus — India set up the Indian Tsunami Early Warning System (ITEWS) at INCOIS Hyderabad (2007)
Tribal Communities of A&N Islands
The A&N Islands are home to some of the world's most isolated tribal communities — designated as Particularly Vulnerable Tribal Groups (PVTGs):
| Tribe | Island | Population | Status |
|---|---|---|---|
| Sentinelese | North Sentinel Island | ~50–500 (unknown) | Most isolated people on Earth; contact forbidden by law |
| Jarawa | South Andaman, Middle Andaman | ~400–500 | Contact in recent decades; road (ATR) bisects territory — major concern |
| Onge | Little Andaman | ~100–150 | Severely declined from ~670 (1901) |
| Great Andamanese | Strait Island (relocated) | ~60–70 | Critically endangered; originally 5,000+ |
| Shompen | Great Nicobar | ~200–400 | Least contacted; forest-dwelling hunter-gatherers |
Legal protection:
- Andaman and Nicobar Islands (Protection of Aboriginal Tribes) Regulation, 1956 — prohibits trespass into tribal reserves
- North Sentinel Island: 3 nautical mile exclusion zone; photography prohibited
- 2018 incident: American missionary John Allen Chau killed by Sentinelese while attempting contact — highlighted continued protection
- The Great Nicobar Development Project has raised concerns about impact on Shompen territory
Great Nicobar Island — Holistic Development Project
Project Overview
| Feature | Detail |
|---|---|
| Approved by | NITI Aayog; Cabinet approval process (2022–2023) |
| Total investment | ~₹72,000 crore (phased; first phase ~₹31,000 crore) |
| Components | (1) Transhipment Port at Galathea Bay; (2) International Airport; (3) Township; (4) Defence and Security installations |
| Area involved | ~166 km² of forest land (requires diversion of forests including pristine rainforest) |
| Timeline | Phase I target: 2030–2035 |
Rationale
- Strategic: India positions forces to monitor Malacca Strait and Six Degree Channel; reduce Chinese influence in A&N seas; INS Baaz expansion
- Economic: Transhipment port would capture container traffic currently going to Colombo and Singapore
- Development: Boost employment and economic activity in remote island
Environmental Controversy
| Concern | Detail |
|---|---|
| Forest diversion | ~130 km² of primary tropical rainforest — among the most biodiverse in India |
| Leatherback sea turtle | Galathea Bay beaches: most important nesting site in India for leatherback turtle (largest reptile); port threatens nesting |
| Shompen tribal territory | Development will irreversibly affect the last hunter-gatherers |
| Coral reefs | Dredging for port approaches will damage fringing reefs |
| Seismic risk | Great Nicobar is in Seismic Zone V — highest risk |
The project received Forest Clearance Stage I from MoEFCC (2022); environmental groups and scientists have raised detailed objections. As of April 2026, the project is at an early implementation stage.
Strategic Significance of A&N Islands
| Strategic Asset | Significance |
|---|---|
| INS Baaz (Campbell Bay, Great Nicobar) | India's southernmost naval air station; monitors Six Degree Channel |
| INS Jarawa (Port Blair) | Naval base; Fleet HQ Andaman |
| Ten Degree Channel | Major sea lane from Bay of Bengal to Indian Ocean — monitored |
| Proximity to Malacca Strait | A&N Islands are ~150 km from Aceh; any vessel entering/exiting Malacca passes near |
| Chinese naval expansion | China's presence in Myanmar, Bangladesh, Sri Lanka monitored from A&N |
| QUAD strategy | A&N nodes in India's Maritime Domain Awareness network |
Lakshadweep
Physical Overview
| Feature | Data |
|---|---|
| Total islands | 36 (12 atolls, 3 reefs, 5 submerged banks; plus small islets) |
| Inhabited islands | 11 |
| Total area | 32.62 km² — India's smallest UT |
| Capital | Kavaratti |
| Location | Arabian Sea; 200–440 km off Kerala coast |
| UT status | Since 1956 (as Laccadive, Minicoy and Amindivi Islands; renamed Lakshadweep 1973) |
Island Groups
| Group | Location | Islands |
|---|---|---|
| Amindivi Islands | Northern group | Amini, Kadmat, Kiltan, Chetlat, Bitra |
| Lakshadweep Islands | Central group | Kavaratti, Agatti, Androth, Kalpeni, Pitti |
| Minicoy | Southern, isolated | Minicoy (closest to Maldives) |
Bitra Island: Smallest inhabited island in India (0.10 km²)
Androth Island: Largest island in Lakshadweep (4.9 km²); densely populated
Minicoy: Southernmost; unique culture — linguistically and culturally close to Maldives; Mahl (Dhivehi) language spoken; lighthouse built 1885
Coral Atoll Formation
Lakshadweep islands are coral atolls — ring-shaped coral reefs (or partial rings) enclosing a lagoon:
- Formed over volcanic seamounts (now submerged) — Darwin's Atoll Theory
- Coral polyps build upward as seamount subsides; eventually a ring reef remains around a lagoon
- Islands sit on the reef rim — maximum elevation only 4–8 m above sea level
- This makes Lakshadweep extremely vulnerable to sea-level rise (IPCC projects 0.3–1.0 m rise by 2100)
Ecology
| Feature | Data |
|---|---|
| Coral coverage | ~4,200 km² of reef; Lakshadweep has India's largest contiguous coral reef system |
| Coral bleaching | Severe bleaching events: 1998, 2010, 2016, 2020, 2024 (4th global bleaching event) |
| Lagoon fish | ~600 species; important for subsistence fishing |
| Sea turtles | Green turtle and hawksbill nest on Lakshadweep beaches |
| Pitti Island | Uninhabited sanctuary; major seabird breeding colony; proposed Marine Protected Area |
Coral bleaching caused by sea surface temperature anomalies (El Niño, Indian Ocean warming) — 2024 bleaching is the worst on record globally; Lakshadweep badly affected.
Strategic Significance of Lakshadweep
| Asset | Significance |
|---|---|
| INS Dweeprakshak | Naval station at Kavaratti; patrols Arabian Sea |
| Sea lane position | On the route from Gulf of Oman (Hormuz) toward Malacca Strait |
| India–Sri Lanka–Maldives triangle | Minicoy sits between Maldives and Kerala; critical for monitoring this triangle |
| LRIT | Long-range identification and tracking of ships from Lakshadweep |
Agatti Airstrip
- Agatti Island: Only airstrip in Lakshadweep; connects to Kochi by air
- Critical for emergency access, naval logistics, civilian transport
- Expansion limited by island size
Comparison: A&N Islands vs Lakshadweep
| Parameter | Andaman & Nicobar | Lakshadweep |
|---|---|---|
| Sea | Bay of Bengal | Arabian Sea |
| Total islands | 572 | 36 |
| Inhabited | 38 | 11 |
| Area | 8,249 km² | 32.62 km² |
| Origin | Submerged mountain range (Burmese arc) | Coral atolls on submerged seamounts |
| Geology | Volcanic + sedimentary | Coral (biogenic) |
| Highest point | Saddle Peak 732 m (North Andaman) | ~10 m (coral atoll maximum) |
| Active volcano | Barren Island (only in South Asia) | None |
| Tribal communities | 5 PVTGs (Sentinelese, Jarawa, Onge, Great Andamanese, Shompen) | None (indigenous islanders — not tribal) |
| Religion | Majority Hindu (settlers) | 100% Muslim (Sunni) — indigenous |
| Language | Hindi, Bengali, Tamil, Telugu | Malayalam (Jeseri/Mahl in Minicoy) |
| Climate risk | Earthquake/tsunami (Zone V); cyclones | Sea-level rise (atolls only 4–8 m high) |
| Key strategic base | INS Baaz (Campbell Bay) | INS Dweeprakshak (Kavaratti) |
| Southernmost point | Indira Point (6°45'N) — India's southernmost point | Minicoy (~8°17'N) |
Key Facts for UPSC
- A&N Islands: 572 total; 38 inhabited; 8,249 km²; capital Port Blair; UT since 1956
- Ten Degree Channel: Separates Andaman (north) from Nicobar (south) at 10°N latitude
- Barren Island: South Asia's only active volcano; 135 km NE of Port Blair; Andaman Sea
- Narcondam: Dormant volcano; endemic Narcondam Hornbill (Critically Endangered)
- Indira Point: India's southernmost point (6°45'N); Great Nicobar; partially submerged after 2004 tsunami
- Cellular Jail (Kala Pani): Port Blair; built 1896–1906; National Memorial
- Sentinelese: North Sentinel Island; most isolated people on Earth; 3 nautical mile exclusion zone
- Great Nicobar Project: ₹72,000 crore; transhipment port + airport; forest diversion + leatherback turtle threat
- INS Baaz: India's southernmost naval air station; Campbell Bay, Great Nicobar
- Lakshadweep: 36 islands; 11 inhabited; 32.62 km² — India's smallest UT; capital Kavaratti
- Lakshadweep religion: 100% Muslim (Sunni) — uniquely homogeneous UT
- Coral atolls: Lakshadweep islands formed by Darwin's atoll formation theory; only 4–8 m above sea level
- Androth: Largest island in Lakshadweep (4.9 km²); Bitra: Smallest inhabited island in India
- Minicoy: Southernmost Lakshadweep island; Mahl language; cultural ties with Maldives
- 2024 coral bleaching: 4th global mass bleaching event; Lakshadweep badly affected — worst on record
- Six Degree Channel: Between Great Nicobar and Sumatra; India's southern maritime limit
- Agatti: Only airstrip in Lakshadweep
- Ross Island: Renamed Netaji Subhash Chandra Bose Island in 2018
The Andaman & Nicobar (A&N) archipelago has 572 total islands (including islets and rocks), of which only 38 are permanently inhabited. Total area is ~8,249 km². The capital is Port Blair (South Andaman). A&N became a Union Territory in 1956.
The Ten Degree Channel (10°N latitude) separates the Andaman Island group (north) from the Nicobar Island group (south). The Duncan Passage (~48 km wide) separates South Andaman from Little Andaman, and the Six Degree Channel separates Great Nicobar from Sumatra, Indonesia. [UPSC Prelims 2014]
Barren Island (135 km NE of Port Blair) is the only active volcano in South Asia — a caldera-type stratovolcano. It is part of the Andaman–Sumatra volcanic arc (Sunda Arc). Significant eruptions include 1787, 1991, 2017–2020, and 2024–2025. The island is uninhabited. [UPSC Prelims 2018]
Narcondam Island is a dormant volcano ~150 km NE of Port Blair. It is the only habitat in the world for the Narcondam Hornbill (Rhyticeros narcondami) — a Critically Endangered endemic species found nowhere else on Earth. The island is a protected Wildlife Sanctuary.
Indira Point (6°45'N) on Great Nicobar Island is India's southernmost point. It was partially submerged during the 2004 Indian Ocean Tsunami (December 26, 2004), which caused ~3,500 deaths in the A&N Islands alone and lowered the land around Indira Point by ~4 m.
Saddle Peak (732 m) on North Andaman is the highest point in the entire Andaman & Nicobar archipelago. Landfall Island is the northernmost point of the A&N Islands.
The Sentinelese of North Sentinel Island are considered the most isolated people on Earth. Their population is unknown (estimated 50–500). A 3 nautical mile exclusion zone is enforced; contact is prohibited by law under the Andaman and Nicobar Islands (Protection of Aboriginal Tribes) Regulation, 1956.
The A&N Islands host 5 Particularly Vulnerable Tribal Groups (PVTGs): Sentinelese (North Sentinel), Jarawa (South and Middle Andaman), Onge (Little Andaman), Great Andamanese (Strait Island — relocated), and Shompen (Great Nicobar). Great Andamanese are critically endangered with only ~60–70 individuals remaining.
The Great Nicobar Island Holistic Development Project (NITI Aayog, 2022) involves a total investment of ~₹72,000 crore for a transhipment port at Galathea Bay, an international airport, a township, and defence installations. It requires diversion of ~166 km² of forest and raises concerns about leatherback sea turtle nesting and Shompen tribal territory.
INS Baaz at Campbell Bay, Great Nicobar, is India's southernmost naval air station. It monitors the Six Degree Channel through which any vessel entering or leaving the Malacca Strait must pass — making the A&N Islands strategically critical.
Lakshadweep has 36 islands (12 atolls, 3 reefs, 5 submerged banks, plus islets), of which only 11 are inhabited. Its total land area is 32.62 km² — making it India's smallest Union Territory. The capital is Kavaratti. The islands are 100% Muslim (Sunni) in population.
Lakshadweep islands are coral atolls formed by Darwin's Atoll Theory: coral polyps built upward on volcanic seamounts (the Chagos-Lakshadweep Ridge, linked to the Reunion Hotspot) as the seamounts subsided, leaving ring-shaped reefs enclosing lagoons. The islands are only 4–8 m above sea level, making them extremely vulnerable to sea-level rise.
Androth Island (4.9 km²) is the largest island in Lakshadweep. Bitra Island (0.10 km²) is the smallest inhabited island in India. Agatti Island is the only island in Lakshadweep with an airport. Minicoy, the southernmost island, is culturally close to the Maldives and its people speak the Mahl (Dhivehi) language.
Lakshadweep experienced severe coral bleaching events in 1998, 2010, 2016, 2020, and 2024 (the 4th global mass bleaching event — worst on record globally). The islands host ~4,200 km² of coral reef — India's largest contiguous coral reef system.
The 9° Channel separates the main Lakshadweep islands from Minicoy Island to the south; the 8° Channel separates Minicoy from the Maldives. The 11° Channel separates the Aminidivi Islands (north) from the Canannore (Kannur) Island group.
Related Chapters
Coastline, Coastal Plains, and Indian Islands
India's 11,098.81 km coastline (revised April 2025), western and eastern coastal plains, and island territories — Andaman & Nicobar and Lakshadweep.
Marine Geography of India
India's marine geography — EEZ (2.37 million km²), UNCLOS zones, ocean currents, coral reefs (bleaching), mangroves (Sundarbans), deep-sea mining, Blue Economy, and marine fisheries.
Indian Ocean — Oceanography and Maritime Significance
Tribes of India