Great, now I need to review Kaliningrad, that odd piece of non-conterminous Russia on the Baltic Sea.

The town of Baltiysk, just outside Kaliningrad, is the only Russian Baltic Sea port said to be “ice-free” all year round, and the region hence plays an important role in maintenance of the Baltic Fleet.

The Kaliningrad Oblast was an exclave of the Russian Soviet Federative Socialist Republic and with the collapse of the Soviet Union in 1991 it became separated from the rest of Russia by independent countries. This isolation from the rest of Russia became even more pronounced politically when Poland and Lithuania became members of NATO and subsequently the European Union in 2004. All military and civilian land links between the region and the rest of Russia have to pass through members of NATO and the EU.
https://en.wikipedia.org/wiki/Kaliningrad