river, an important tributary of the Euphrates River (Tigris-Euphrates river system). It rises in the mountains of southeastern Turkey near Diyarbakır and flows southeastward to Al-Ḥasakah, Syria, where it receives its main tributary, the Jaghjagh; it then meanders south to join the Euphrates downstream from Dayr az-Zawr. The Khābūr (“Source of Fertility”) has a total length of about 200 miles (320 km). The climate of the drainage basin is warm and semiarid to arid. The river has long been important for irrigating the fertile Al-Ḥasakah region of northeastern Syria. Following World War II, the construction of new dams and an improved canal network increased the total cultivated area to more than 4,000,000 acres (1,600,000 hectares). The Khābūr River valley is now Syria's leading wheat-producing district and an important source of cotton, barley, rice, sesame, and vegetables.