Poland's eastern border touches which Russian exclave, physically separated from mainland Russia?

The correct answer is Kaliningrad, formally the Kaliningrad Oblast, a Russian exclave on the Baltic Sea coast bordered by Poland to the south and Lithuania to the north and east, with no land connection to the rest of the Russian Federation. It was formerly the German city of Königsberg, part of East Prussia, and became Soviet territory after the Second World War under the Potsdam Agreement of 1945, subsequently being renamed Kaliningrad after Soviet leader Mikhail Kalinin. Its unusual location, surrounded by NATO and EU member states Poland and Lithuania, makes it a strategically significant and heavily militarised Russian outpost, frequently discussed in the context of Baltic security and NATO's eastern flank. Crimea, offered as a distractor, is a peninsula on the Black Sea, annexed by Russia from Ukraine in 2014, and is geographically nowhere near Poland, making it a clearly separate geopolitical topic despite being another prominent Russia-related territorial issue in current affairs. Sakhalin is a large island in Russia's Far East, near Japan, entirely on the opposite side of the country from Poland and unrelated to Baltic geography. Chukotka is Russia's easternmost region, facing Alaska across the Bering Strait, again geographically as distant from Poland as possible within Russian territory. A common exam confusion is mixing up Russia's various exclaves, islands and disputed territories, since several appear in current-affairs questions simultaneously, Crimea for Ukraine-related news and Kaliningrad for Baltic and NATO-related news. The essential revision anchor is: Kaliningrad sits between Poland and Lithuania on the Baltic Sea and is Russia's only exclave bordering EU and NATO territory directly, distinguishing it clearly from Crimea, Sakhalin and Chukotka.