- a city in the W Russian Federation in Europe, NE of Kaliningrad on the Nemen River: formerly in East Prussia; peace treaty (1807) between France, Prussia, and Russia.
- a town in W Russia, in the Kaliningrad Region on the Neman River: scene of the signing of the treaty (1807) between Napoleon I and Tsar Alexander I; passed from East Prussia to the Soviet Union in 1945
