Croydon? Didn't that used to be an airport?
I'm far too young to know anything about that, but about 10 years ago I worked with an air traffic controller who had started his career at Croydon. (must have been late 1940's early 1950's)
Amongst the tales he told me about the place was that as a trainee ATCO on nightshift he was left alone in the tower while his mentor went home to bed... "Nothing to it...telephone if you need any help".