English geographical insult

I'm in search of some fairly specialized English knowledge, here. I need the name of a town or region that a rather snobbish upper-class Englishman (in 1939) might use as an example of provincial narrow-mindedness. [ETA: Of the middle-class rather than rural or working-class variety.] He's putting down someone who has just expressed an attitude he considers unsophisticated, and the line will be something like "You sound like a vicar's daughter from X."

Any suggestions?