The border starts in the west at the western tripoint with Tibet, China, proceeding from there broadly southwards across Mount Gipmochi and down to the Jaldhaka River. It then utilises this river for a period before turning south-westwards and then east via a series of irregular overland lines that broadly follow the foothills of the Himalayas, notably Dangme Chhu peak. It then turns to the north, turns west near Sakteng, briefly utilising the Tawang Chu and Nyamjang Chu, before turning north up to the eastern Chinese tripoint.