Checkpoint Charlie was a crossing point between East and West Berlin during the Cold War. It was the only crossing point between East and West Berlin that was open to foreigners and members of the Allied forces. The checkpoint was named after the letter "C" in the NATO phonetic alphabet and was
From Wikipedia
Checkpoint Charlie was the Western Bloc's name for the best-known Berlin Wall crossing point between East Berlin and West Berlin during the Cold War (1947–1991), becoming a symbol of the Cold War, representing the separation of East and West.