Gangpo Ri (4130m) is of special significance for Tibetans as the legendary birthplace of the Tibetan people, where Chenresig in the form of a monkey mated with the white demon Sinmo to produce the beginnings of the Tibetan race. The Monkey Cave, where all this took place, can be visited near the summit of the mountain. Do it in the spirit of a demanding half-day walk in the hills, as the cave itself is somewhat uninspiring.
The most direct trail leads up from the Sang-ngag Zimche Nunnery, climbing about 550m to the cave. The walk up will take about two hours – bring plenty of water. The walk up Gangpo Ri is part of a long pilgrim route, which local Tibetans make each year on the 15th day of the fourth lunar month.