The Yarlung valley is considered the cradle of the Tibetan people. The story goes that Avalokiteshvara (Chenresig), the Bodhisattva of Compassion, descended from the heavens to the Land of Snows long ago in the form of a monkey. He meditated in a cave on the slopes of Gangpo Ri, before being drawn from his solitude by Sinmo, a white demoness. It seems she got his attention by sitting outside his cave and weeping - oldest trick in the book, but one that is especially effective with a Bodhisattva of Compassion. One thing led to another and before too long they had six children - the beginnings of the Tibetan race. A strip of land nearby (now less than romantically known as 'Commune No 9') is the site of the legendary 'first field in Tibet'.

The contours of the valley shelter a wealth of other such legends. The mountain of Lhabab Ri is said to be the site where the first of the Tibetan kings, Nyentri Tsenpo, descended from heaven on a sky cord, whereupon he was recognised by 12 local chieftains. subsequent Tibetan kings all ascended back to heaven using the handy sky cord until Drigum Tsenpo, whose name means 'slain by pollution', accidentally cut the cord in a show of marksmanship. From this time the remains of Tibetan kings were earth-bound and buried in the funerary mounds of Chongye.

Then in 1943 three Americans fell from the sky. They had lost their bearings and run out of fuel while on a mission flying supplies from India to Kunming over 'The Hump', China's only supply line during WWII. They managed to bail out of their B-24 bomber and landed on mountain slopes above Tsetang. They finally made it to Lhasa and then safely back home to Idaho but only after they narrowly escaped a mob of Tibetans furious that foreigners had been high enough to look down on the Dalai Lama.