Originating at Angsi Glacier in western Tibet, southeast of Mount Kailash and Lake Manasarovar, it later forms the South Tibet Valley and Yarlung Tsangpo Grand Canyon before passing into the state of Arunachal Pradesh, India. Downstream from Arunachal Pradesh the river becomes far wider and is called the Siang. After reaching Assam, the river is known as Brahmaputra. From Assam, the river enters Bangladesh at Ramnabazar. From there until about 200 years ago it used to flow eastward and joined the Meghna River near Bhairab Upazila. This old channel has been gradually dying. At present the main channel of the river is called Jamuna River, which flows southward to meet Ganges, which in Bangladesh is called the Padma.