Neris (, , ) is a river rising in Belarus. It flows through Vilnius ( Lithuania) and becomes a tributary of the Neman River (Nemunas) at Kaunas (Lithuania). Its length is . For the river runs through Belarus, where it is called Viliya, and runs through Lithuania, where it is called Neris.
The Neris connects two old Lithuanian capitals – Kernavė and Vilnius. Along its banks are burial places of the pagan Lithuanians. At from Vilnius are the old burial mounds of Karmazinai, with many mythological stones and a sacred oak.