India covers 3.3 million square kilometers, making it the seventh largest country in the world. Stretching from the Himalayas in the north to tropical rainforests in the south, the country contains nearly every type of landscape found on Earth: snow-capped peaks, vast river plains, deserts, plateaus, dense coastlines, and remote island chains. This diversity shapes everything from climate and agriculture to where people live and how they move.
Size, Borders, and Position
India occupies most of the South Asian subcontinent, bordered by the Arabian Sea to the west, the Bay of Bengal to the east, and the Indian Ocean to the south. Its total coastline, including islands, spans roughly 11,099 kilometers based on the most recent survey by the National Hydrographic Office. Gujarat has the longest mainland coastline at about 2,341 km, followed by Tamil Nadu and Andhra Pradesh.
On land, India shares borders with six countries. Bangladesh has the longest border at 4,097 km, followed by China at 3,488 km, Pakistan at 3,323 km, Nepal at 1,751 km, Myanmar at 1,643 km, and Bhutan at 699 km. Mountains define the northern and northeastern boundaries, while flatter terrain and rivers mark the borders with Bangladesh and Pakistan.
The Northern Mountains
The Himalayas form a massive wall along India’s northern edge. They contain more than 110 peaks above 7,300 meters, including Mount Everest at 8,849 meters on the Nepal-China border. Within India, the range runs through the states of Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, and Arunachal Pradesh.
The Himalayas are organized into four parallel belts running roughly east to west. The outermost belt, the Siwalik Range, consists of lower foothills and is the youngest geologically. North of that lie the Lesser Himalayas, with moderate elevations and deep valleys. The Great Himalaya Range forms the highest belt, carrying the tallest peaks. Beyond that, the Tethys Himalayas transition into the Tibetan Plateau. These mountains block cold Central Asian air masses from reaching the plains below and force moisture-laden monsoon winds upward, triggering heavy rainfall on the southern slopes.
The Northern Plains
South of the Himalayas, a broad, flat expanse of land stretches across northern India. These plains were built over millions of years by sediment carried down from the mountains by three major river systems: the Indus, the Ganga, and the Brahmaputra. Together, the Ganga-Brahmaputra-Meghna basin alone drains about 1.1 million square kilometers, making it the largest river basin in the country and accounting for more than 43% of the catchment area of all major Indian rivers.
The Ganga basin covers roughly 861,000 square kilometers within India, flowing east through Uttar Pradesh, Bihar, and West Bengal before emptying into the Bay of Bengal. The Brahmaputra drains about 194,000 square kilometers, winding through Assam’s wide valley. These plains are among the most fertile and densely populated regions on Earth, supporting intensive agriculture that feeds hundreds of millions of people. The flat terrain and rich alluvial soil make this the country’s agricultural heartland, producing wheat, rice, and sugarcane on a massive scale.
The Peninsular Plateau
South of the plains, the landscape rises into a broad, ancient plateau that makes up much of central and southern India. The Deccan Plateau is the dominant feature here, a tableland flanked by two mountain ranges: the Western Ghats along the Arabian Sea coast and the Eastern Ghats along the Bay of Bengal coast. The Western Ghats are higher and more continuous, receiving enormous monsoon rainfall on their seaward side. The Eastern Ghats are lower and more broken up by river valleys.
The Deccan Plateau itself sits on some of the world’s most well-known volcanic rock formations, called the Deccan Traps. These formed roughly 65 to 67 million years ago when enormous lava flows covered the western and central parts of the subcontinent. Layer upon layer of basalt solidified into a stepped landscape (the word “trap” comes from a Scandinavian word for stairs). This volcanic geology created mineral-rich soils, particularly the black cotton soils that dominate parts of Maharashtra and Karnataka.
Further east, the Chota Nagpur Plateau in Jharkhand and surrounding states is one of India’s richest mineral zones, with significant deposits of iron ore, coal, and other resources that support the country’s industrial economy.
The Thar Desert
In the northwest, the Thar Desert (also called the Great Indian Desert) covers about 200,000 square kilometers of rolling sand hills, primarily in Rajasthan but extending into Pakistan’s Sindh and Punjab provinces. Annual rainfall ranges from just 100 mm in the western sections to about 500 mm in the east, making it one of the most arid regions in South Asia.
The Thar is bordered by the Indus River plain to the west, the Punjab Plain to the north, the Aravalli Range to the southeast, and the marshy Rann of Kutch to the south. Unlike the Sahara, the Thar is relatively populated. Communities have adapted to water scarcity over centuries, relying on seasonal lakes, deep wells, and increasingly on canal irrigation from the Indus system.
The Coastal Plains
Narrow strips of low-lying land run along both sides of the peninsula between the plateau and the sea. The western coastal plain, squeezed between the Western Ghats and the Arabian Sea, is narrower and receives heavier rainfall. It includes the Konkan coast in Maharashtra and Goa, and the Malabar coast in Kerala. Kerala’s coast is famous for its backwater lagoons, a network of interconnected canals, rivers, and lakes that run parallel to the shoreline.
The eastern coastal plain is wider because the Eastern Ghats sit farther from the shore. Major river deltas form here, including those of the Godavari (basin area: about 313,000 sq km), Krishna (about 259,000 sq km), and Cauvery (about 81,000 sq km). These deltas are prime rice-growing regions. The eastern coast also bears the brunt of cyclones forming in the Bay of Bengal, particularly in Odisha, Andhra Pradesh, and Tamil Nadu.
The Island Territories
India has two major island groups with very different origins. The Andaman and Nicobar Islands sit in the Bay of Bengal, about 1,200 km from the mainland. The Andamans comprise more than 300 islands and the Nicobars consist of 19. Both groups are part of a great island arc, essentially the above-sea extensions of submarine mountain ridges connecting the mountain ranges of Myanmar to the north with the Indonesian archipelago to the south. Barren Island in the northern Andamans has an active volcano that erupted multiple times in the late 20th and early 21st centuries. The islands have coral-fringed coasts with deeply indented shorelines. The Andaman and Nicobar Islands account for 3,084 km of India’s total coastline.
The Lakshadweep Islands lie in the Arabian Sea off the coast of Kerala. They are coral atolls, formed by coral reef growth on submerged volcanic foundations. Lakshadweep is much smaller, with a coastline of about 145 km, and sits just a few meters above sea level, making it especially vulnerable to rising seas.
Climate Zones
India’s geography creates a remarkable range of climates. The country contains tropical rainforest climates in the Western Ghats and northeast, tropical monsoon climates across much of the peninsula, hot desert and semi-arid climates in Rajasthan and parts of Gujarat, humid subtropical conditions across the northern plains, temperate oceanic climates in the mid-altitude hills, and cold desert climates in the high-altitude regions of Ladakh. The highest elevations in the Himalayas experience polar-like conditions year-round.
The monsoon dominates India’s climate calendar. From June through September, moisture-laden winds from the Indian Ocean sweep northward, delivering the vast majority of the country’s annual rainfall. The Western Ghats and the northeastern state of Meghalaya receive some of the heaviest rainfall on the planet during these months. The winter months are generally dry across most of the country, though the northwest receives some rainfall from western weather systems originating over the Mediterranean.
Major River Basins
India has 12 major river basins, each draining more than 20,000 square kilometers. Himalayan rivers like the Ganga, Brahmaputra, and tributaries of the Indus are fed by both snowmelt and monsoon rain, giving them year-round flow. Peninsular rivers like the Godavari, Krishna, Narmada (basin area: about 99,000 sq km), and Cauvery depend almost entirely on monsoon rainfall and can shrink dramatically in the dry season.
An important geographic divide determines which direction these rivers flow. The Western Ghats act as a continental divide for peninsular India. Most major peninsular rivers, including the Godavari, Krishna, and Cauvery, originate on the western side of the Ghats but flow eastward across the plateau to empty into the Bay of Bengal. Only the Narmada and Tapi flow westward into the Arabian Sea, following ancient rift valleys rather than the general slope of the plateau. This east-flowing pattern is why the eastern coastal plain has large, fertile deltas while the western coast remains narrow and steep.