Chernyakhovsk (Russian: Черняхо́вск; German: Insterburg ; Lithuanian: Įsrutis; Polish: Wystruć) is a town and the administrative center of Chernyakhovsky District of Kaliningrad Oblast, Russia, located at the confluence of the Instruch and the Angrapa Rivers, forming the Pregolya. Population: 40,464 (2010 Census preliminary results); 44,323 (2002 Census); 39,622 (1989 Census).