A river system refers to a river along with its tributaries. India is a land of many rivers like the Ganga, Yamuna, Godavari, Narmada, Kaveri, Indus etc. Each of these rivers along with their tributaries and distributaries form huge river systems. There are two kinds of rivers in India: Himalayan and Peninsular. Himalayan rivers are perennial and snow-fed with long, wide courses. Peninsular rivers are seasonal, rain-fed and have shorter courses. Most of the peninsular rivers flow towards the east and drain into the Bay of Bengal like the Kaveri, Godavari, Mahanadi, Krishna etc. However, Narmada and Tapi (peninsular) flow towards the west, and drain into the Arabian Sea. The three major Himalayan rivers are Indus, Brahmaputra, Ganga. A little more than one-third of the Indus is found in India, in the Jammu-Kashmir region. The Ganga drains the Gangetic or Northern plains, while the Brahmaputra drains North-east India. 

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