River Tsang Po originates at Lake Mansarovar in Western Tibet and runs 2000 miles across the Tibetan plateau at an altitude of 11,000 – 12,000 feet. Then it takes a sharp turn to the south around Namche Barwa, the highest unclimbed peak in the world, and cuts through the great Himalayan Range, carving for itself a deep and inaccessible gorge before it enters India. From here the river is called the Siang as it enters into the virgin and till recently forbidden state of Arunachal Pradesh. After cascading down 300 Kms. of grade 4 – 5 rapids the Siang enters Assam at Pasighat and is renamed as the Brahmaputra. The average width of the Brahmaputra is an amazing 10 kilometres.
Till as late as 1930s the source of the mighty Brahmaputra and its links with Tibet and the Tsang Po river were a mystery and enigma. Famous explorations by legends like Kinthup and his predecessors went a long way in solving the mystery of the “missing link”.