Port Blair-the capital of Andaman and Nicobar Islands, is located in which one of the following islands?

1. Physiography of Indian Island Groups (basic)

India’s maritime territory is punctuated by two distinct island groups that differ drastically in their geological 'DNA'. In the east, the Andaman and Nicobar Islands in the Bay of Bengal are essentially the visible tips of a submerged mountain range—often considered a continuation of the Arakan Yoma mountains of Myanmar INDIA PHYSICAL ENVIRONMENT, Chapter 2, p.15. This archipelago consists of approximately 572 islands and islets, ranging from large inhabited landmasses to tiny rocky outcrops. They are broadly divided into the Andaman group in the north and the Nicobar group in the south, separated by a wide stretch of water known as the Ten Degree (10°) Channel.

Geologically, these islands are a mix of tectonic and volcanic activity. For instance, Barren Island in the Nicobar chain holds the distinction of being India’s only active volcano Geography of India, Physiography, p.66. The terrain is rugged and mountainous; the highest point in the entire archipelago is Saddle Peak (738 m), located in North Andaman. The administrative and economic heartbeat of the territory is Port Blair, situated on the east coast of South Andaman Island. It was historically developed as a hub due to its naturally protected harbor, which remains a vital gateway for maritime trade today.

In contrast, the Lakshadweep Islands in the Arabian Sea have a completely different origin. They are not mountain peaks, but rather coral islands (atolls) built by tiny marine organisms over vast periods of time INDIA PHYSICAL ENVIRONMENT, Chapter 2, p.15. These islands are much smaller in number (around 36 inhabited islands) and are generally low-lying and flat compared to the mountainous Andamans. Despite their geological differences, both groups share an equatorial climate characterized by high humidity and heavy convectional rainfall.

Feature	Andaman & Nicobar	Lakshadweep
Location	Bay of Bengal	Arabian Sea
Origin	Tectonic/Volcanic (Submerged Mountains)	Coral (Atolls)
Major Peak	Saddle Peak (North Andaman)	Generally flat/low elevation
Separated by	Ten Degree Channel	9° & 11° Channels

Sources: INDIA PHYSICAL ENVIRONMENT, Chapter 2: Structure and Physiography, p.15; Geography of India, Physiography, p.66

2. Major Channels and Water Passages (basic)

In Indian physical geography, channels are narrow bodies of water that connect two larger seas or separate two landmasses. The most iconic of these are named after their latitudinal positions. The Ten Degree Channel is a critical maritime feature that separates the Andaman Islands in the north from the Nicobar Islands in the south Geography of India, Majid Husain, p.66. This channel is approximately 150 km wide and serves as a major shipping lane in the Bay of Bengal. Understanding these passages is essential because they define the administrative and physical boundaries of our island territories. Looking closer at the Andaman archipelago, it is primarily composed of three main islands: North, Middle, and South Andaman (collectively known as Great Andaman), along with Little Andaman to the south. Port Blair, the capital of the Union Territory, is strategically located on the east coast of South Andaman INDIA PHYSICAL ENVIRONMENT, Geography Class XI, p.15. This location was chosen for its naturally protected harbor, making it the administrative and economic nerve center. Further south, the Nicobar group consists of islands like Car Nicobar and Great Nicobar, the latter of which houses Indira Point, the southernmost point of Indian territory Geography of India, Majid Husain, p.66. Beyond the Ten Degree Channel, other significant passages include the Duncan Passage, which separates South Andaman from Little Andaman, and the channels in the Arabian Sea (like the Eight and Nine Degree Channels) that delineate the Lakshadweep islands. These waterways are not just lines on a map; they are vital corridors for biodiversity and international trade, ensuring India's strategic presence in the Indian Ocean region.

Sources: Geography of India, Majid Husain, Physiography, p.66; INDIA PHYSICAL ENVIRONMENT, Geography Class XI, Structure and Physiography, p.15

3. Key Volcanic and Topographic Features (intermediate)

While the Indian mainland is geologically stable and lacks active volcanism, the Andaman and Nicobar Islands present a much more dynamic landscape. This archipelago is essentially the visible peaks of a submerged mountain range—an extension of the Arakan Yoma in Myanmar. Because these islands sit near the subduction zone where the Indo-Australian plate slides beneath the Eurasian plate, they host India’s only volcanic features.

The most significant of these is Barren Island, which holds the title of the only active volcano in India and South Asia. Located in the Andaman Sea, it saw a major eruption in 1991 and most recently spewed lava and ash in 2017 Physical Geography by PMF IAS, Volcanism, p.156. In contrast, Narcondam Island, situated about 150 km northeast of Barren Island, is considered an extinct volcano, characterized by a destroyed crater wall Physical Geography by PMF IAS, Volcanism, p.156. These volcanic origins distinguish some of the smaller islands from the larger ones, which are primarily composed of sedimentary rocks or coral deposits INDIA PHYSICAL ENVIRONMENT, Chapter 2, p.15.

Topographically, the islands are defined by high mountain peaks that offer a dramatic vertical profile. To master this for the exam, you should associate each major peak with its specific island:

• Saddle Peak (738 m): The highest point in the entire archipelago, located in North Andaman.
• Mount Diavolo (515 m): The primary peak of Middle Andaman.
• Mount Koyob (460 m): Situated in South Andaman.
• Mount Thuiller (642 m): The highest peak of the Nicobar group, located on Great Nicobar island.

INDIA PHYSICAL ENVIRONMENT, Chapter 2, p.15.

Administratively and economically, Port Blair is the heart of the region. It is located on the east coast of South Andaman. This location was chosen specifically for its naturally protected harbor, which provides a safe haven for ships and serves as the primary maritime gateway for the territory. The islands also feature equatorial vegetation due to their proximity to the equator and the heavy convectional rainfall they receive throughout the year INDIA PHYSICAL ENVIRONMENT, Chapter 2, p.15.

Sources: Physical Geography by PMF IAS, Volcanism, p.156-157; INDIA PHYSICAL ENVIRONMENT, Geography Class XI (NCERT 2025 ed.), Chapter 2: Structure and Physiography, p.15

4. Tribal Groups and Anthropological Survey (intermediate)

The Andaman and Nicobar Islands are home to some of the world's most ancient and isolated indigenous communities. These tribes are broadly classified into two distinct ethnic groups based on their origins: the Negrito hunters and gatherers of the Andaman Islands (Great Andamanese, Onge, Jarawa, and Sentinelese) and the Mongoloid groups of the Nicobar Islands (Nicobarese and Shompen). While the islands are endowed with lush tropical rainforests and a mix of Indian and Myanmarese flora Majid Husain, Regional Development and Planning, p.90, the indigenous population has faced significant demographic shifts. Most current inhabitants are migrants from mainland India, Bangladesh, and Myanmar, causing the tribal population to dwindle relatively Majid Husain, Physiography, p.68.

The Anthropological Survey of India (AnSI) plays a critical role in monitoring these communities. For instance, the Jarawas (also known as the Angs) are considered one of the most endangered tribes globally. Data from the AnSI Andaman & Nicobar Centre shows a delicate but positive trend: the Jarawa population grew from 266 in 2001 to 429 by 2016 Majid Husain, Cultural Setting, p.26. In contrast, the Sentinelese remain the most isolated, famously resisting all outside contact on North Sentinel Island. In the Nicobar group, which is largely of coral origin, the Shompens live in the interior of Great Nicobar, while the Nicobarese are more integrated into the modern economy, focusing on coconut and arecanut as cash crops Majid Husain, Physiography, p.68.

The geographic separation of these groups is marked by the Ten Degree Channel, a 150 km wide stretch of water that divides the Andaman group from the Nicobar group Majid Husain, Regional Development and Planning, p.90. Understanding the distribution of these tribes is essential for appreciating the cultural diversity and the conservation challenges within India's maritime territories.

Tribal Group	Location	Ethnic Stock
Jarawa, Onge, Sentinelese	Andaman Islands	Negrito
Shompen, Nicobarese	Nicobar Islands	Mongoloid

Sources: Geography of India (Majid Husain, 9th ed.), Regional Development and Planning, p.90; Geography of India (Majid Husain, 9th ed.), Physiography, p.68; Geography of India (Majid Husain, 9th ed.), Cultural Setting, p.26

5. Strategic and Maritime Significance (exam-level)

In strategic geography, a location’s value is determined by its ability to control trade routes, provide security, and offer administrative stability. The Andaman and Nicobar Islands, an archipelago of 556 islands, serve as India’s primary maritime gateway in the Bay of Bengal Geography of India, Majid Husain, Regional Development and Planning, p.90. These islands are not just physical landmasses but act as an 'unsinkable aircraft carrier,' allowing India to monitor the Strait of Malacca, one of the world's busiest maritime choke points. The archipelago is broadly divided into the Andaman group and the Nicobar group, separated by the Ten Degree Channel, which is approximately 150 km wide Geography of India, Majid Husain, Physiography, p.66.

While the islands are numerous, South Andaman Island holds the highest strategic and administrative priority. It houses Port Blair, the capital city, situated on its eastern coast. This location was chosen primarily because of its naturally protected harbor, which is essential for maritime trade and naval operations. While North Andaman is known for the archipelago's highest point, Saddle Peak, and Middle Andaman features Mount Diavolo, South Andaman remains the most developed and populated hub, hosting the Veer Savarkar International Airport INDIA PHYSICAL ENVIRONMENT, Geography Class XI (NCERT 2025 ed.), Chapter 2: Structure and Physiography, p. 15.

The maritime significance extends to the southernmost tip of India at Indira Point (on Great Nicobar Island), which places India in close proximity to Southeast Asia. Historically, strategic locations like these have determined the fate of empires; just as the plains of Panipat were the gateway to Delhi because they offered a path through difficult terrain, the Andaman islands serve as the modern 'maritime gates' to the Indian Ocean Rajiv Ahir, A Brief History of Modern India, India on the Eve of British Conquest, p.61.

Feature	North Andaman	Middle Andaman	South Andaman
Key Landmark	Saddle Peak	Mount Diavolo	Port Blair & Cellular Jail
Significance	Highest elevation	Largest land area	Administrative & Maritime Hub

Sources: Geography of India, Majid Husain, Regional Development and Planning, p.90; Geography of India, Majid Husain, Physiography, p.66; INDIA PHYSICAL ENVIRONMENT, Geography Class XI (NCERT 2025 ed.), Chapter 2: Structure and Physiography, p.15; Rajiv Ahir, A Brief History of Modern India, India on the Eve of British Conquest, p.61

6. Zonal Mapping of the Great Andaman Group (exam-level)

To master the geography of the Bay of Bengal islands, we must zoom into the Great Andaman Group. While many people think of 'Andaman' as a single entity, it is actually a tightly clustered archipelago. The 'Great Andaman' refers to the primary group of islands, which are geologically considered to be the submerged extensions of the Arakan Yoma mountain range of Myanmar. This group is divided into three distinct zones: North Andaman, Middle Andaman, and South Andaman. Together, they form the backbone of the Union Territory's administrative and ecological landscape INDIA PHYSICAL ENVIRONMENT, Chapter 2, p. 15.
Each zone has its own unique geographic 'personality' and significance. North Andaman is the rugged high-ground, hosting Saddle Peak, which at 738 meters is the highest point in the entire archipelago. Middle Andaman is the largest island by area and is home to Mount Diavolo. South Andaman, however, is the heartbeat of the region. It houses the capital city, Port Blair, which was established on its east coast due to its naturally protected deep-water harbor—an essential feature for maritime trade and defense Geography of India (Majid Husain), Physiography, p. 66.
Beyond topography, these islands carry immense historical weight. South Andaman is the site of the Cellular Jail, where India's freedom fighters endured 'Kala Pani' (exile across black waters). Today, this zone serves as the primary gateway to the islands, featuring the Veer Savarkar International Airport and acting as the hub for tourism and administration Exploring Society: India and Beyond (NCERT), Geographical Diversity of India, p. 22.

Island Zone	Key Geographic Feature	Significance
North Andaman	Saddle Peak (738 m)	Highest elevation in the Andaman & Nicobar chain.
Middle Andaman	Mount Diavolo (515 m)	Largest island in the Great Andaman group.
South Andaman	Port Blair & Mount Koyob (460 m)	Administrative capital, primary harbor, and historical hub.

Sources: INDIA PHYSICAL ENVIRONMENT (NCERT 2025 ed.), Chapter 2: Structure and Physiography, p.15; Geography of India (Majid Husain), Physiography, p.66; Exploring Society: India and Beyond (NCERT), Geographical Diversity of India, p.22

7. Solving the Original PYQ (exam-level)

Now that you have mastered the physiographic divisions of the Indian islands, you can see how the Andaman archipelago is organized into distinct clusters. This question tests your ability to pinpoint the administrative heart of the territory within the Great Andaman group. Having studied the sequence from North to South, you should recognize that while the islands form a continuous chain, the strategic and economic center is historically situated in the most accessible southern reaches of the main group, serving as the primary link to the Indian mainland via the Veer Savarkar International Airport.

To arrive at the correct answer, think like a geographer: a capital city requires a deep-seated harbor and strategic proximity to trade routes. While North Andaman is famous for its elevation (Saddle Peak) and Middle Andaman is the largest by land area, South Andaman provides the naturally protected harbor essential for maritime logistics. Therefore, Port Blair is logically situated on the east coast of (D) South Andaman. As established in INDIA PHYSICAL ENVIRONMENT, Geography Class XI (NCERT 2025 ed.), this location acts as the gateway to the entire archipelago.

UPSC often uses the close proximity of these islands to create confusion. A common trap is selecting Little Andaman; however, you must recall that Little Andaman is separated from the Great Andaman group by the Duncan Passage and is much more isolated. Similarly, North and Middle Andaman are characterized more by their ecological features than by administrative density. By eliminating the northern ecological hubs and the isolated southern island, you can confidently identify the developed administrative hub as South Andaman.