Bailey–Morshead exploration of Tsangpo Gorge

North of Himalaya, the Yarlung Tsangpo River flows east through the Tibetan Plateau and then turns south into a series of massive gorges in Himalayan mountains.

[note 1] Kinthup, a Lepcha man from Sikkim employed as a pundit, had provided some evidence that the Tsangpo flowed into the Dihang (which is a tributary of the Brahmaputra) but he was not widely believed.

By ascending the Dibang river and crossing the Yonggyap Pass (29°13′00″N 95°35′00″E / 29.21667°N 95.58333°E / 29.21667; 95.58333[8]) and the Himalayan watershed into Tibet, they reached the Dihang and started up the Gorge.

[9] When they were at Lagung, just east of Namcha Barwa, they were arrested by the Nyerpa of Pome who took them to Showa on the Po Tsangpo river.

By following this river downstream to the west and then north they reached the Rong Chu valley where Bailey discovered a tall blue poppy – now known as Meconopsis baileyi – at a forest edge.