Ili River
The Ili River treaty of 638 AD formalized the division of the Western Turkic Kaganate (552–638 AD) into the Nushibi and the Dulu. It also established the Ili River as the border between the two states. In the 21st century, increasing need for water in both China and Kazakhstan makes the management of the cross-border Ili River a topic of concern for environmentalists and politicians in Kazakhstan (who feel that their country may not get enough water flowing in from China any more).