Yarlung Tsangpo River (around 3,848 km)
is the longest river of Tibet. It is the upper stream of the Brahmaputra River. Originating at Angsi Glacier in western Tibet, southeast of Mount Kailash & Lake Manasarovar, it later forms the South Tibet Valley and Yarlung Tsangpo Grand Canyon before passing into the state of Arunachal Pradesh, India.
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