A new interactive mobile phone app has been launched which people can use to discover which buildings were used by spies in London during the Second World War.
The app, developed with war veterans and archive material, has been developed to mark the 70th anniversary of the disbanding of Special Operations Executive (SOE).
It combines video and audio interviews, images, original documents and Geolocation mapping to reveal information about the buildings and people involved in secretive work during the war.
The SOE was created in 1940 to encourage, support and supply resistors in occupied countries. It disbanded in January 1946.
It took over buildings and estates across Britain as training schools or as clandestine wireless stations, but its secret headquarters was 64 Baker Street in London, now a disused lighting shop.
Other notable buildings featured on the app include:
The General Post Office Film Unit in Savile Row, which was re-purposed to make films for the war effort.
An underground shooting range next to Baker Street Tube Station where operatives could practice their markmanship.
Thatched Barn near Elstree was used as SOE's Camouflage Section. Everything from a tree trunk concealing a radio to false documents and authentic clothing were produced here. The building has since been used as a set in movies The Saint and The Prisoner.
4 Carlton Gardens, where French leader Charles de Gaulle spent much of his wartime exile
Michael House in Baker Street was the Head Office of Marks and Spencer. SOE took over the top two floors. To avoid the staff of M&S knowing about the secret offices, SOE staff entered through a mews at the back of the building.
The Natural History Museum's Demonstration Room. New gadgets and devices for agents to use in the field were showcased including exploding animal dung, boats which folded into briefcases and disguises.
Among those who helped the SOE was Joyce Aylard. She was stationed at RAF Eastcote in London, where she worked as a Bombe operator during the war.
Initially devised by Alan Turing in 1939, the Bombe machine was the device that enabled British code breakers to decipher German Enigma-machine encrypted messages.
My father was upset that he never knew what I did during the war. He knew I was in the The Women's Royal Naval Service but that was all- he never knew what I did and that upset him apparently. It was just one of those things. It couldn't happen now but in those days, you just did not talk.
Meanwhile Jean Argles and her sister Patricia both worked for the SEO but were unable to tell each other about the nature of their work until some years after the war.
We had to go to Baker Street where the headquarters of the organisation, the underground movements in Europe, were managed from and it was terribly top-secret.
The free app can be downloaded on iTunes as Spooks, Spies and Videotape: London's Secret War and onAndroid as London's Secret WWII.