With a land area of 3,287,263 km (1,269,219 sq mi) consisting of diverse ecosystems, India has many rivers systems and perennial streams. The rivers of India can be classified into four groups – Himalayan, Deccan, Coastal, and Inland drainage. The Himalayan rivers, mainly fed by glaciers and snow melt, arise from the Himalayas. The Deccan rivers system consists of rivers in Peninsular India, that drain into the Bay of Bengal and the Arabian Sea. There are numerous short coastal rivers, predominantly on the West coast. There are few inland rivers, which do not drain into sea.
Most of the rivers in India originate from the four major watersheds in India. The Himalayan watershed is the source of majority of the major river systems in India including the three longest rivers–the Ganges, the Brahmaputra and the Indus. These three river systems are fed by more than 5000 glaciers. The Aravalli range in the north-west serves the origin of few of the rivers such as the Chambal, the Banas and the Luni rivers.
