The Himalayas (meaning 'Abode of Snow') are the world’s youngest, highest, and longest fold mountain system, formed through the collision of the Indian Plate with the Eurasian Plate. They continue to rise due to ongoing plate tectonics.

The Himalayas extend about 2400 km with varying width (200–500 km). They show unique features such as syntaxial bends, very high peaks, steep southern slopes, asymmetrical topography, and a link with Central Asian ranges through the Pamir Knot.

The Tuting-Tidding Suture Zone (TTSZ) lies in the Eastern Himalayas where the mountains bend sharply southward and connect with the Indo-Burma Range. The Himalayas are divided north-to-south into Trans Himalayas, Greater Himalayas (Himadri), Lesser Himalayas (Himachal), and Outer Himalayas (Shiwalik).

The Himalayas are divided into three major ranges: the Greater Himalayas (Himadri), the Lesser Himalayas (Himachal), and the Outer Himalayas (Shiwalik). Each range differs in elevation, composition, width, and topography, but together they form the backbone of the Indian subcontinent's physiography.

The Himalayas are longitudinally divided into Western (Indus to Kali), Eastern (Kali to Brahmaputra), and North-Eastern Hills (Purvanchal). Each section has distinct physiography, culture, and strategic significance.

The Himalayas are divided longitudinally into Western, Eastern, and North-Eastern Hills (Purvanchal). Each subdivision has unique peaks, passes, valleys, and strategic significance.

The Western Himalayas (Indus to Kali) and Eastern Himalayas (Kali to Dihang) differ in slopes, climate, snowline, and prominent peaks due to their latitudinal location and physiography.

A pass is a natural gap or break in high rugged terrain, providing connectivity across Himalayan ranges. Passes in the Himalayas have historically been crucial for trade, cultural exchange, and strategic defense.

The Himalayas are vital for India’s climate, defense, rivers, hydroelectricity, biodiversity, agriculture, tourism, and minerals. They act as a climatic barrier, a source of rivers, a storehouse of forests and minerals, and support cultural and economic life.

The snowline is the lower altitudinal limit of permanent snow, which varies in the Himalayas due to latitude, precipitation, slope, and topography. The Karakoram Anomaly refers to the unusual stability or growth of glaciers in the Karakoram, unlike the retreat observed elsewhere.

The Himalayas house some of the world’s largest glaciers outside the polar regions, especially in the Karakoram range. Glaciers are important sources of perennial rivers like Ganga, Yamuna, and Indus.

The Northern Plains are the youngest physiographic feature of India, covering less than one-third of the area but supporting over 40% of the population. Formed by alluvial deposits of the Indus, Ganga, and Brahmaputra systems, they are among the world’s largest alluvial tracts.

The Northern Plains are divided into Bhabar, Tarai, Bhangar, and Khadar. These represent different stages of alluvial deposition and drainage characteristics, influencing agriculture, vegetation, and settlement.

The Punjab Plains form the western part of the Northern Plains, shaped by the Indus and its tributaries. Characterized by doabs, Bets, shifting sand dunes, and the Haryana Tract, they represent a fertile but diverse physiographic region.

The Northern Plains are regionally divided into Punjab, Rajasthan, Ganga, and Brahmaputra Plains. Rajasthan Plains include the Thar Desert, Ganga Plains form the largest alluvial stretch with the world’s biggest delta, and Brahmaputra Plains are rich in biodiversity and riverine features.

The Northern Plains, with fertile soils and perennial rivers, are agriculturally rich, culturally significant, and useful for navigation. They are often called the ‘Granary of India’.

The Thar Desert, the 9th largest desert in the world, lies in northwestern India. Though geologically part of the Peninsular Plateau, it is classified under plains due to its flat surface. Locally known as Marusthali, it is marked by aridity, sand dunes, saline lakes, and seasonal streams.

The Peninsular Plateau is the largest physiographic unit of India. It is a stable tableland made of old crystalline igneous and metamorphic rocks, associated with the Gondwana land. Rich in minerals, it has diverse physiographic features like plateaus, hill ranges, valleys, and rift structures.

The Peninsular Plateau is divided into the Central Highlands, the Deccan Plateau, and the North-Eastern Plateau. Each region has unique physiography, elevation, geology, and resource distribution, making it the mineral and agricultural heart of India.

The hill ranges of Peninsular India are among the oldest mountains in the world. They are residual, denuded mountains with local significance, acting as watersheds, influencing rainfall, and serving as biodiversity hotspots.

The Peninsular Plateau, though older and eroded compared to the Himalayas, has important peaks spread across Western Ghats, Eastern Ghats, Aravallis, Satpura, Nilgiris, Khasi, and Deccan ranges. These peaks are significant for geography, ecology, and culture.

Passes in the Peninsular Plateau are important corridors through the Western Ghats and Aravallis, facilitating trade, transport, and historically battles. They also connect different cultural and ecological zones.

The Peninsular Plateau is the storehouse of India’s mineral wealth, agricultural soils, hydropower sites, and hill stations, making it a vital physiographic unit for economy, agriculture, and tourism.

The Coastal Plains of India are narrow strips of lowlands lying along both sides of the Peninsular Plateau. They stretch for about 7515 km, covering nine states and four union territories. They vary in width and physiography from north to south.

India’s coastal plains are classified into Western Coastal Plains (Arabian Sea) and Eastern Coastal Plains (Bay of Bengal). They differ in physiography, rainfall, deltas, ports, and economic significance.

The Andaman & Nicobar Islands, located in the Bay of Bengal, are known as the 'Emerald Islands'. They extend from Landfall Island in the north to Indira Point in the south. They are volcanic in origin and ecologically rich.

Lakshadweep, Minicoy, and Amindivi form India’s smallest Union Territory in the Arabian Sea, made entirely of coral deposits. India also has significant riverine, barrier, and offshore islands like Majuli, Sriharikota, and Rameshwaram.