Three Western Air Corridors to Berlin were established after the Yalta (February 1945) and Potsdam (July 1945) Conferences and formalized on 31 December 1945. The three corridors were 20 English miles wide, from Hamburg, Hannover and Frankfurt-am-Main to Berlin, terminating in Gatow, Tegel and Templehof Airfields, West Berlin. The final mission was flown on 29 September 1990, just a few days before formal German unification and the disappearance of the Air Corridors. The Berlin Air Route Traffic Control Centre was finally closed on 31 December 31, 1994. In between those dates is a fascinating, and very overlooked, history of over 10,000 clandestine reconnaissance flight operations against both the Soviets and East Germans in the heart of the Cold War.
The author, Kevin Wright, states, in the final chapter (Chapter 8 – An Outstanding Achievement),