This is the only book, written by experts with first-hand knowledge, to examine in detail the clandestine reconnaissance operations over East Germany during the Cold War era. Between 1945 and 1990 the wartime Western Allies mounted some of the most audacious and successful photographic intelligence collection operations using their freedom of access to the internationally agreed airspace of the Berlin Air Corridors and Control Zone that passed over a large area of East Germany. The operations were authorised at the highest political levels and conducted in great secrecy used modified transport and training aircraft disguised as normal transport and training flights exercising the Allies' access rights to Berlin and its environs. For nearly 50 years these flights gathered a prodigious amount of imagery that was analysed by intelligence analysts to provide the western intelligence community with unique knowledge of the organisation and equipment of the Warsaw Pact forces. Using recently declassified materials and extensive personal interviews with those involved at all levels this book provides, for the first time, a detailed account and analysis of these operations and their unique contribution to the Cold War intelligence picture.