Chernyshevskoye (Russian: Черныше́вское; German: Eydtkuhnen, from 1938 Eydtkau; Lithuanian: Eitkūnai; Polish: Ejtkuny) is a settlement in Nesterovsky District in the eastern part of Kaliningrad Oblast, Russia, on the border with Lithuania.
Between Chernyshevskoye and Lithuanian Kybartai is an important 24-hour border crossing point on the A229 principal road and the railway route connecting Kaliningrad with Moscow through the European Union member Lithuania and Belarus. Until 1945 a part of the German province of East Prussia, Eydtkuhnen was the easternmost terminus of the Prussian Eastern Railway finished in 1860 connecting Berlin with the Saint Petersburg – Warsaw Railway in the Russian Empire. To continue their voyage, passengers e.g. of the Nord Express had to change over to a Russian gauge train.
The railway connection decisively promoted Eydtkuhnen's development: The Lutheran church built by Friedrich Adler was consecrated in 1889, the settlement received town privileges in 1922. Nevertheless Eydtkuhnen was devastated during the Russian invasion of East Prussia in 1914 and again in 1945 during the East Prussian Offensive of the Red Army. With the implementation of the Oder-Neisse line after World War II, the area became part of the Soviet Union.