One source says the Nyenchen Tanglha Mountains range is about in length. Its highest point is located to the northwest of Lhasa. The range is parallel to the Himalayas in the Transhimalayas, and north of the Brahmaputra River. Another source says the Nyenchen Tanglha Mountains extend from Nyêmo County in the west to Ranwu County in the east. Its highest peak is Mount Nyenchen Tanglha at. The southern side of the Nyenchen Tanglha Mountains is precipitous, and falls by around, while the northern side is fairly level and descends about. Most of the mountains are below. They contain 7080 glaciers covering an area of. The Nyenchen Tanglha Mountains have an average latitude of 30°30'N and a longitude between 90°E and 97°E. Together with the Gangdise Shan located further west, it forms the Transhimalaya which runs parallel to the Himalayas north of the Yarlung Tsangpo River. The Drukla Chu river rises in the Nyenchen Tanglha Mountains, where it is called the Song Chu river, and joins the Gyamda Chu river. The combined rivers run about southeast to the Yarlung Tsangpo river.
Subranges
The range is divided into two main parts: the West and East Nyenchen Tanglha, with a division at the high Tro La Pass near Lhari Town.
West Nyenchen Tanglha
The West Nyenchen Tanglha lies to the southeast of Namtso. The range trends to the northeast, and forms part of the northern watershed of the Yarlung Tsangpo River. The northeastern section is drained by the Lhasa River, the largest tributary of the Yarlung Tsangpo. West Nyenchen Tanglha includes the four highest peaks in the range, all above : Mount Nyenchen Tanglha, Nyenchen Tanglha II, Nyenchen Tanglha III and Jomo Gangtse, all located in Damxung County of Lhasa. West Nyenchen Tanglha separates the basins of the Yarlung Tsangpo in the south from the endorheic basins of the Changtang in the north.
East Nyenchen Tanglha
East Nyenchen Tanglha, located in Nagqu Prefecture, Chamdo and Nyingchi Prefecture, marks the water divide between the Yarlung Tsangpo to the south and the Nak Chu river to the north. The rugged and heavily glaciated range counts more than 240 peaks over, culminating with Sepu Kangri which has a 2,213 m topographic prominence and is away from a higher point. Large areas of the eastern sector are snow-covered. Two-thirds of the glaciers, accounting for five-sixths of the area, lie in the eastern section. This section receives the southwest monsoons, which enter the Tibetan plateau at the Yarlung Zanbo river's Grand Bend. The air is forced up by the terrain, and yields the highest rainfall and moistest air of the plateau, which feeds the development of glaciers. There are thirty-two glaciers that are over long. Kyagquen Glacier is the largest, covering and extending for. The end of the Qiaqing glacial tongue is at in an area of mountain forests. The glacier foot is at. According to the Langzhou Glaciers Research Institute, there are a total of 2,905 glaciers in the range covering a total area of. Most of the peaks in East Nyenchen Tanglha, sometimes called the Alps of Tibet, are unclimbed. Sepu Kangri itself was attempted twice by Chris Bonington and Charles Clarke in 1997 and 1998, about which experience Bonington and Clarke wrote the book Tibet's Secret Mountain: The Triumph of Sepu Kangri. The summit was finally reached on 2 October 2002 by Mark Newcomb and Carlos Buhler.
