Northeast of Ulugh Muztagh an endorheic basin with several important lakes (Aqqikol, Ayakkum, Jingyu, etc.) is located. The basin is bounded by the main range of the Kunlun in the south, and by the more or less parallel range, the Altyn-Tagh, in the north. Much of the basin is officially protected as the Altun Shan Nature Reserve.