Cutting southward across the Siwalik Hills, it splits into two branches, the Geruwa on the left and Kauriala on the right near Chisapani to rejoin south of the Indian border and form the proper Ghaghara. Other tributaries originating in Nepal are the West Rapti, the Kali (or Mahakali) and the little Gandak. It flows southeast through Uttar Pradesh and Bihar states to join the Ganges downstream of the town of Chhapra, after a course of . Sarayu river is stated to be synonymous with the modern Ghaghara river or as a tributary of it.