A series of
mountain ranges run along the northern edge of the
Tibetan Plateau, with the
Kunlun Mountains located in the West. About halfway across the south side of the
Tarim Basin, the Altyn-Tagh Range diverges northeast while the Kunluns continue directly east, forming a relatively narrow "V". Inside the "V" are a number of
endorheic basins. The eastern end of the Altyn-Shan is near the
Dangjin Pass on the
Dunhuang-
Golmud road in far western
Gansu. East of the Altyn-Tagh the
border range rises to the
Qilian Mountains. The range separates the Tarim Basin, to the north, and
Lake Ayakkum, to the south. The range can be divided into three portions. The southwest portion borders the
Kunlun Mountains and is very rugged, with peaks reaching more than and many perennial snow fields. The central portion is lower in elevation, around . The eastern portion is higher in elevation, about and consists of a group of smaller ranges oriented in a south-east to north-west trend. Along the northern side of the mountains ran the main
Silk Road trade route from
China proper to the Tarim Basin and westward. The Altyn-Tagh and Qilians were sometimes called the
Nan Shan ('south mountains') because they were south of the main route. Near the east end of the Altyn-Shan, the Gansu or
Hexi Corridor ends and the Silk Road splits. One branch follows the Altyn-Tagh along the south side of the Tarim Basin while the other follows the north side. The southwestern part of the Altyn-Tagh range reaches snowy peaks of up to , although it descends to an average of in the narrow middle and eventually rises up to average as it meets the Qilian Mountains. There are a dearth of rivers and streams in these mountains, due to the aridity of the region. The western portion has some small streams that either head north into the desert or south into Lake Ayakkum. The remainder of the range is lacking in rivers. == Intermontane endorheic basins ==