The River Brahmaputra has its source in the Chemayungdung glacier of the Kailash Mountain (Himalayas in Tibet) and flows towards the east. It is known as the River Tsangpo in Tibet.
Among the total length of 2900 km, it flows for about 885 km in India. It enters India after taking a sharp bend southward (near Namcha Barwa Peak) and enters Arunachal Pradesh where it is known as River Dihang.
In India it flows from east to west and in Arunachal Pradesh it joint with River Dibang and River Lohit. After the confluence it is known as river Brahmaputra and flows through Assam. At Dhubri, the Brahmaputra takes southward-turn and enters Bangladesh, where it is known as river Jamuna. River Jamuna then meets with river Padma and drains to the Bay of Bengal.
The important tributaries of the River Brahmaputra are Dibang, Lohit, Subansiri, Tista, Dhansiri, Kopili, etc.