Kaliningrad

The Kaliningrad Oblast includes the historical lands of Sambia, Lower Prussia, and Lithuania Minor, also known as Little Lithuania or Prussian Lithuania.

An excerpt from the article 24 facts about Kaliningrad

About 1/3 of the perimeter area (including a significant part of the coast and the entire Russian part of the Vistula Spit) are restricted access zones. A five-kilometer strip near the border is prohibited for foreigners to enter (they must have special passes).

The Kaliningrad Oblast is part of the North-Western Federal District established in 2000.