The Tuul River flows through central and northern Mongolia. It is 704 km long and has a catchment area of 49,840 km2. It flows through Khentii, Tuv, Selenge aimags and Ulaanbaatar. The height of the basin is between 770 and 2800 meters, the highest point is Asralt Khairkhan Mountain at 2799.3 meters above sea level, and the lowest point is the Orkhon-Tuul delta at 770 meters above sea level.