Checkpoint Charlie

After World War II, Germany and Berlin were divided into four occupation zones: an American, a British, a French, and a Soviet occupation zone. The American, British, and French occupation zones became part of the Federal Republic of Germany (BRD, informally: West Germany), while the Russian zone became the German Democratic Republic (DDR, informally East Germany). Between the Federal Republic and the DDR ran the heavily guarded German-German border, and the Berlin Wall surrounded West Berlin, which was completely enclosed by the DDR.
If one wanted to travel by road from the Federal Republic to East Berlin, they were required to first travel to West Berlin via the so-called Transit Highways – the only road connections between the Federal Republic and West Berlin – and from there to East Berlin. Checkpoint Charlie was the third checkpoint that had to be passed en route. It was named after the third letter of NATO's spelling alphabet. Checkpoint Alpha was the border crossing at Helmstedt on the German-German border. Checkpoint Bravo was located on the highway near Dreilinden, on the border between Potsdam and West Berlin.
Checkpoint Charlie was the only checkpoint where the diplomatic corps and other foreigners (everyone except West Berliners, West Germans, and residents of the Allied Control Council) could enter East Berlin by road. With public transport, the nearby Bahnhof Friedrichstraße was the only way for tourists to enter the country.

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