The Yarlung Valley is formed by the Yarlung Tsangpo River and refers especially to the district where it joins with the Chongye River, and broadens out into a large plain about 2 km wide, before they flow north into the Yarlung Tsangpo River or Brahmaputra. It is situated in Nedong County of Lhokha Prefecture (Ch. Shannan Prefecture) in the Tibet Autonomous Region of China. The capital of Lhokha Prefecture, Zêtang, in the Yarlung Valley, is one of Tibet's largest cities, and is 183 km southeast of Lhasa.Coordinates: 29°12′N 91°46′E / 29.200°N 91.767°E
It was originally well-forested and suitable for agriculture. The Tsetang district is famous for its apples and pears.
The Yarlung and the adjoining Chongye Valley formed the original seat of the Yarlung dynasty of Tibetan kings and controlled important ancient trade routes into India and Bhutan. The first Tibetan Emperor, Songtsen Gampo (605 or 617? - 649), moved the capital to Lhasa after greatly expanding his territories and power.
The valley, often referred to as the "cradle of Tibetan civilisation", is only 72 km (45 mi) long, but contains a number of important castles, monasteries, temples, meditation caves, peaks and stupas. There are three renowned power places (ne-sum), Sheldrak, Tradruk, and Yumbu Lagang or (Yungbulakang Palace). Also, there are three major stupas which serve as receptacles for sacred relics (ten-sum): Takchen Bumpa, Gontang Bumpa, and Tsechu Bumpa.