One of the reasons that Berlin was a hotbed of spy activity during the 1950s, ‘60s and ‘70s was that it was not just on the front line of the Cold War, but was actually behind the “enemy” line. Prior to the end of World War II, the Allied powers decided that Germany would be split into four administrative zones, one each for the Soviets, the American, the British, and the French. At the same time, Berlin, as the German capital, was also to be divided into four administrative zones, even though it was located deep within the Soviet-governed portion of Germany.
Prior to the erection of the Berlin Wall in 1961, people could move freely within the city of Berlin, giving spies the opportunity to meet with informants and gather information from a variety of sources. This gave rise to Berlin’s reputation for being the site of more espionage activity than any place else in the world (which was also an exciting prospect for Hollywood film makers).
When the Wall went up, however, the fun began, giving rise to the National Security Agency’s top secret listening post on Teufelsberg, a hill built from the rubble of war-ravaged Berlin. Fortunately, it was considerably more sophisticated than an earlier attempt to tap into communications between the Soviets and East Germans.
In an effort to uncover Soviet intelligence passed along an underground hub of telecommunications cables adjacent to the U.S. sector in Berlin, the CIA built a 900-foot long tunnel, hooked up to the cables and started “downloading” the information. Completed in March 1955, the tunnel was shut down in April 1956 when the Soviets, who learned of its existence from one its spies, began tunneling down to it from their side. Trying to embarrass the Americans, the Soviets concocted a fanciful and widely-circulated account of Soviet technicians surprising Americans as they sipped coffee in the tunnel. In reality, the American personnel had plenty of time to shut down operations and get out before the Soviet troops got down and into the facility.
The legend of the tunnel lived long after its location was actually forgotten. I arrived in Berlin in July 1967, and “old-timers” who had been there a year or two before me regaled newks with their tales of actually knowing the personnel who worked in the tunnel. ASA voice intercept operators sitting within the confines of the tunnel with their headsets on and being surprised when the Russians broke through was the most commonly told tale. In reality, a heavy torch-proof steel door was closed to keep the Soviets out and all they could do was cut the cables.
Another tale, which I actually fell for, was that the tunnel was discovered because the CIA hadn’t thought about how snow over the heated area of the tunnel would melt, creating an easily followed trail from west to east. Hey, like our friends at CNN, I had my source, man.