Bagmati is a perennial river fed by a number of springs. Flowing through the Indo-Nepal borders, this 250 km long river takes it origin from the mountains north-east of the Nepal valley in the Himalayas
During its course, Bagmati River flows along the districts of Samastipur, Muzaffarpur and Darbhanga. The river is also known by two different names - Siyari and Kareha.
Tilkesvar is the place where Bagmati joins the Kosi River. The tributaries that join this river are the Lalabakaya, Lamakhola, Chani and Bhurengi. The river finally merges with the Ganges.