A while ago, whilst I was sourcing early 20th century maps of Sheffield on commercial online sites, I came across German military maps of Sheffield made in 1938-. They were based on OS, but printed with additional military information marking sites of strategic interest.
I didn't have more than a passing interest in them at the time and didn't take note of which site they were on. I know NLS have a set online for Scotland, but does anyone know where I can find English sheets?
thanks in anticipation.