Public access to wartime mapping was restricted by the Directorate of Military Survey in the early 1970s after concern was expressed at the likelihood of illegal immigrants being flown in 'under the radar' from the continent. Indeed, in November 1971 a quick-witted farmer rammed a Cherokee at Kimbolton aerodrome which had been flown in by a Syrian pilot - it contained 4 Indian and 1 Pakistani passengers. The Syrian had tried to bribe the farmer after trying to run off, but the farmer went for him with a spanner....
If you see an aeronautical map of the early 1950s, it looks as though someone has fired a shotgun at the map of East Anglia - there were well over 100 aerodromes! When I flew my PPL qualifying cross-country back from Ipswich to Cranfield, there were about a dozen aerodromes within 3 miles of my track on one side or another - and I was advised not to use them as fixes due to the ease of mis-identification.