Reichsautobahn Berlin-Königsberg

Berlinka (Russian: Берлинка) is the informal Polish and Russian name given to sections of the unfinished Reichsautobahn Berlin-Königsberg, which was a pre-World War II German Reichsautobahn project to connect Berlin with Königsberg in East Prussia. In the late 1930s, the sections near these two cities were finished, but not the larger section in between. The German demand in 1939 to run this road across the Polish Corridor with extraterritorial status and Poland's refusal to allow this was an important element in the tensions that led to the start of World War II. After the war, the German Democratic Republic, the People's Republic of Poland and the Soviet Union's Kaliningrad Oblast inherited the remnants.

Eastern Prussia had been separated from Germany following the Treaty of Versailles by the Polish Corridor of the Second Polish Republic. By 1939 Poland had already refused demands made by Nazi Germany, including one for an extraterritorial corridor within the Corridor. This fact was eventually used by Adolf Hitler as one of the pretexts for the German invasion of Poland in 1939.

The road was planned under the Weimar Republic, but was partially constructed during the 1930s and early 1940s by the Third Reich.

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