Episode 7 of 10
7/10 Off the Map. The first step to success in any military campaign is a good map. During the Second World War, intelligence officers prepared meticulously detailed maps for the D-Day landings using a combination of aerial photography, old tourist guides and holiday snaps. Mike Parker discovers how Germany, and later the Soviet Union, compiled maps of Britain often more detailed than our own. And he visits a Cold War nuclear bunker, one of the many sites that until recently were simply blank spaces on Ordnance Survey maps.