During the early years of the Cold War (a period after World War II with tension between powers in the Western Bloc and powers in the Eastern Bloc), West Berlin was a geographical loophole through which thousands of East Germans fled to the democratic West. In response, the Communist East German authorities built a wall that totally encircled West Berlin. It was thrown up overnight, on August 13,1961.

The Communist government of the German Democratic Republic (GDR, or East Germany) actually built a barbed wire and concrete wall (Antifascistischer Schutzwall or anti-fascist bulwark) between East and West Berlin in 1961.

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