Mahananda River, river in northern India and Bangladesh. It rises in the Darjiling (Darjeeling) Hills in extreme northern West Bengal state. The river flows south through a rich agricultural area in Bihar state, enters West Bengal state, flows past Ingraj Bazar, and then continues southeastward into Bangladesh to join the Ganges (Ganga) River at Godagari Ghat after a 225-mile (360-km) course. The Mahananda forms in its upper course an important eastward linguistic boundary between the Bengali- and Hindi-speaking areas.