⛰ Geography: Physical India

🏔 Passes and islands

India’s gateways — the Himalayan passes that carried traders, pilgrims and armies, the tunnels and high roads built under and over them — and the more than 1,300 islands in her seas, from Barren Island’s volcano to Majuli on the Brahmaputra.

Maps show India’s boundaries as officially depicted by the Government of India. Pins mark approximate locations.

🏔 Gateways through the mountains

The Himalayas and the ranges beside them were a formidable barrier — crossed only at a few passes, which became roads for trade, faith and war.

  1. A barrier with a few gates

    The Himalayas, with other ranges, acted as a formidable physical barrier in the past. Except for a few mountain passes — the Khyber, the Bolan, the Shipkila, the Nathula, the Bomdila — it was difficult to cross them, and this helped give the Indian subcontinent its own regional identity.

  2. For at least 2,500 years

    The Khyber Pass

    One of the main passes through the Hindu Kush. Many invaders used it to enter the Subcontinent; for at least 2,500 years it was also a major trade route linking the Subcontinent to Central Asia, and the route Buddhist scholars and monks travelled. The Hindu Shahis, who controlled it, resisted several invasions before the Ghaznavids overran them.

  3. Shipki La: where the Satluj breaks through

    The Satluj flows almost parallel to the Indus for about 400 km before entering India. It passes through the Shipki La on the Himalayan ranges and comes out into the Punjab plains — an antecedent river, older than the mountains it cuts.

  4. Rohtang: where two rivers begin

    The Beas rises at Beas Kund near the Rohtang Pass, 4,000 m above sea level, and the Ravi rises west of the pass in the Kullu hills. Near Rohtang the Dhaula Dhar range meets the Pir Panjal.

  5. 1981; 2015

    Lipulekh and Nathu La: the road to Kailash

    Indian pilgrims to Kailash Mansarovar cross into Tibet by two routes — the Lipulekh pass and Nathu La. The Yatra resumed through both in 2025, after a hiatus of nearly five years, and continued in 2026.

  6. Ghats: gaps for the railways

    The Western Ghats are crossed only through gaps or passes (ghats). On the hilly peninsula, railway tracks are laid through low hills, gaps or tunnels.

🚇 Tunnels and high roads

The Border Roads Organisation, set up in 1960, keeps the high passes open — and now tunnels under them, so valleys once cut off for months stay connected all year.

  1. May 1960

    The Border Roads Organisation

    Established in May 1960 to speed up economic development and strengthen defence preparedness by improving strategically important roads along the borders. It also clears snow in the high-altitude areas.

  2. 3 October 2020

    Atal Tunnel under the Rohtang

    The world’s longest highway tunnel, 9.02 km long, built by the BRO in the Pir Panjal range at about 3,000 m (10,000 feet). It links Manali to the Lahaul-Spiti valley all year — a valley earlier cut off for about six months each year by snow — and cuts the Manali–Leh road by 46 km. The Prime Minister dedicated it to the nation on 3 October 2020.

  3. 2021

    Umling La: the world’s highest motorable road

    The BRO built and black-topped a road through the 19,024-foot Umlingla Pass in Ladakh — the 52-km Chisumle–Demchok road. Guinness World Records recognised it on 16 November 2021 as the world’s highest motorable road, beating a Bolivian road that reaches 18,953 feet.

  4. 9 March 2024

    Sela Tunnel to Tawang

    Built by the BRO at 13,000 feet on the Tezpur–Tawang road in Arunachal Pradesh, using the New Austrian Tunnelling Method, it gives Tawang all-weather connectivity across the Sela Pass. It was dedicated to the nation on 9 March 2024.

  5. Khardung La

    NCERT’s chapter on transport shows the Khardung La pass in Ladakh as an example of the border roads the BRO builds and keeps open.

🏝 India’s islands

More than 1,300 small islands — the Andaman and Nicobar group in the Bay of Bengal, the coral islands of Lakshadweep in the Arabian Sea, and islands in India’s great rivers.

  1. More than 1,300 islands

    India has more than 1,300 small islands, in two major groups — the Andaman and Nicobar Islands in the Bay of Bengal and the Lakshadweep Islands in the Arabian Sea. With them, India’s coastline is 7,517 km; the mainland alone has 6,100 km.

  2. The Andaman and Nicobar Islands

    About 572 islands and islets in the Bay of Bengal, in two groups — the Andaman in the north and the Nicobar in the south — separated by the Ten Degree Channel. They are believed to be the raised parts of submarine mountains; NCERT calls them ‘outposts of India’, keeping an eye on the ocean.

  3. Barren Island: India’s only active volcano

    Some of the smaller Andaman and Nicobar islands are volcanic. Barren Island is the only active volcano in India; it sometimes erupts, sending smoke and lava into the sky.

  4. Saddle Peak and the island summits

    The high points of the Andaman and Nicobar Islands: Saddle Peak (North Andaman, 738 m), Mount Diavolo (Middle Andaman, 515 m), Mount Koyob (South Andaman, 460 m) and Mount Thuiller (Great Nicobar, 642 m).

  5. Lakshadweep: islands of coral

    An archipelago in the Arabian Sea close to the Malabar coast of Kerala, 220–440 km offshore. The whole group is built of coral: there are about 36 islands, of which 11 are inhabited, and the Nine Degree Channel divides it.

  6. Majuli: the largest river island

    Majuli, in the Brahmaputra in Assam, is the largest riverine island in the world. The river’s floods leave fertile silt, and Majuli grows good paddy after them — though the floods’ losses far outweigh such benefits.

  7. Sri Lanka and Maldives: island neighbours

    Sri Lanka and Maldives are the two island countries in the Indian Ocean that are India’s neighbours. Sri Lanka is separated from India by the Gulf of Mannar and the Palk Strait.

  8. 6 April 2025

    The new Pamban Bridge to Rameswaram

    The rail bridge to Rameswaram island is India’s first vertical-lift railway sea bridge: 2.08 km long with 99 spans, and a 72.5-metre span that rises up to 17 metres so ships can sail underneath. It was inaugurated in April 2025.

  9. 1987

    Elephanta Caves

    The ‘City of Caves’ on an island near Mumbai, with huge high reliefs linked to the cult of Shiva.

🚩 Islands in history

A Chola naval base, the Cellular Jail, Netaji’s tricolour of 1943 — and the new names that honour that history.

  1. Gupta era

    Indian traders on Socotra

    In the Gupta era India traded with the Mediterranean world, Southeast Asia and China. Socotra Island in the Arabian Sea was a stop on the way to the Mediterranean markets, and finds there show Indian traders over several centuries.

  2. The Cellular Jail

    Many freedom fighters were jailed on the Andaman Islands, under the most severe conditions, in a prison complex called the ‘Cellular Jail’. It has been preserved to remind us of the sacrifices made so that India could be free.

  3. 1943; 30 December 2018

    Netaji’s tricolour and three new names

    Netaji Subhas Chandra Bose hoisted the tricolour on Indian soil here in 1943. On the 75th anniversary, on 30 December 2018, the Prime Minister announced that Ross Island would be named Netaji Subhas Chandra Bose Dweep, Neil Island Shaheed Dweep and Havelock Island Swaraj Dweep.

  4. 23 January 2023

    21 islands for 21 Param Vir Chakra heroes

    On Parakram Diwas 2023 the 21 largest unnamed islands of the Andaman and Nicobar group were named after the 21 Param Vir Chakra awardees — the largest after the first awardee, the second largest after the second, and so on.

  5. 13 September 2024

    Port Blair becomes Sri Vijaya Puram

    The capital of the Andaman and Nicobar Islands was renamed Sri Vijaya Puram in September 2024, to free the nation from colonial imprints. The Home Minister recalled that the islands once served as a naval base of the Chola Empire.

🌐 Islands of the world

Lakhs of islands of every size — from coral specks to Greenland.

  1. What is an island?

    Pieces of land surrounded by water on all sides, too small to count as continents, are called islands. Continents are surrounded by water too, but are too large to be called islands. There are lakhs of islands on the planet.

  2. Greenland, the largest island

    Greenland is the largest island in the world: you would have to add up the areas of India’s ten largest states to reach its size.

✍ Practise: Passes and islands Exam-style questions and flashcards made from this page. ✍ Take the quiz 🃏 Flashcards ⛰ Geography: Physical India

How we check: geography and history cards use NCERT’s own words; tunnels, high roads, bridges and island names are from the Press Information Bureau; the Kailash Mansarovar routes from the Ministry of External Affairs. Every phrase is found in its source when the page is built.