Knowledge has always been power, which is why spies have been around as long as human civilisation itself. In ancient Egypt spies were known as “the eyes of the Pharoah”, in Persia King Cyrus referred to them as his many “eyes and ears”, and even General Sun Tzu devoted a whole chapter to spies in his famous “The Art of War”.
During the Cold War, Berlin was where East met West, no where else did the Soviet and NATO powers get into such close contact with each other. This is why Berlin is the best place to learn all about the world of spies. You can visit the German Spy Museum on the former border, the very death strip of the Berlin Wall.