Tien Shan

Mountain chain in Central Asia, forming part of the boundary between Kyrgyzstan, southeastern Kazakhstan and China (Xinjiang Uygur autonomous region). The Tien Shan range extends for over 2,400 km/1,500 mi northeast from the Pamirs to the western fringe of the Gobi desert. The principal peaks are Pobeda Peak (7,439 m/24,406 ft) and Khan-Tengri (6,995 m/22,949 ft).

The main ranges of the Tien Shan form a ridge bordering the high plateau that makes up a large part of East Asia. In this area are found the main peaks of the Tien Shan, as well as the largest glaciers, and it is crossed by passes at 3,000–4,000 m (ca.10,000–13,000 ft). Forest occurs from 1,200 m/3,937 ft up to the treeline at 3,000 m/9,843 ft. The chief lakes of the region are Ysuk-Köl (area 6,236 sq km/2,408 sq mi), Sonkel, and Chatyrkel. Non-ferrous and rare metals are found in the mountains, together with coal, oil, and rock-salt. Livestock husbandry is the main economic activity of the indigenous population.

Folding occurred in the Hercynian and earlier periods; subsequent reneplanation was followed by late Tertiary and Quaternary uplifting, which with glaciation and rapid dissection is largely responsible for the present relief.