I’ve never been to Kings Lynn before. Within a couple of miles, but never visited the town until today. And I was told that the Norfolk/Lincolnshire border is the North/South divide, as far as the long/short a sound is concerned. Boston, in Lincolnshire, is only a few miles from Kings Lynn in Norfolk, but there they say ‘bath’ to rhyme with ‘math’, whilst in the Norfolk town they say barth, like every other good Southerner. And most of the bad ones.