Baltiysk (/bɔːlˈtiːsk/ bawl-TEESK) is a seaport town and the administrative center of Baltiysky District in Kaliningrad Oblast, Russia, located on the northern part of the Vistula Spit, on the shore of the Strait of Baltiysk separating the Vistula Lagoon from Gdańsk Bay. It had a population of 33,946 (2021 census); 32,697 (2010 census); 33,252 (2002 census); 27,070 (1989 Soviet census).
Baltiysk, the westernmost town in Russia, is a major base of the Russian Navy's Baltic Fleet and is connected to St. Petersburg by ferry.