File:Issyk-Kul, Kyrgyzstan (6019934565).jpg

English: Tianshan Mountains, Kyrgyzstan

View from Cholpon-Ata across the lake towards Tian-Shan Mountains. Distance is approximately 50mls/80km

The Tian Shan literally "celestial mountains";, also spelled Tien Shan, is a large mountain system located in Central Asia. The highest peak in the Tian Shan is Victory Peak (Jengish Chokusu), 7,439 metres (24,406 ft). Tian Shan lies to the north and west of the Taklamakan Desert in the border region of Kazakhstan, Kyrgyzstan and Xinjiang. In the south it links up with the Pamir Mountains. It also extends into the Chinese province of Xinjiang and into the northern areas of Pakistan, where it joins the Hindu Kush.[ The Tian Shan are a part of the Himalayan orogenic belt, which was formed by the collision of the Indian and Eurasian plates in the Cenozoic era. They are one of the longest mountain ranges in Central Asia and stretch some 2,800 kilometres (1,700 mi) eastward from Tashkent in Uzbekistan.

The highest peak in the Tian Shan is Victory Peak which, at 7,439 metres (24,406 ft), is also the highest point in Kyrgyzstan and is on the border with China. The Tian Shan's second highest peak, Khan Tengri (Lord of the Spirits), straddles the Kazakhstan-Kyrgyzstan border and at 7,010 metres (23,000 ft) is the highest point of Kazakhstan. Mountaineers class these as the two most northerly peaks over 7,000 metres (23,000 ft) in the world.

The Torugart Pass, at 3,752 metres (12,310 ft), is located at the border between Kyrgyzstan and China's Xinjiang province. The forested Alatau ranges, which are at a lower altitude in the northern part of the Tian Shan, are inhabited by pastoral tribes that speak Turkic languages.

The major rivers rising in the Tian Shan are the Syr Darya, the Ili River and the Tarim River. The Aksu Canyon is a notable feature in the northwestern Tian Shan.