This is interesting, peterg,
An article in The Times (27 Dec 2003) by Jim McCue was about families' secret words. He mentions the Nott family in Herefordshire who, after eating their Christmas dinner, claimed to have "come to Stokes's Bridge". Jim McCue, who is a friend of the Nott family, tells that the saying came from a couple of generations ago when the Nott children used to go for a walk, but only as far as the little bridge leading to Mr Stokes's farm. Any further and they would have been too tired to get home. Hence, coming to Stokes's Bridge still means that a Nott can go no further.
That's what Mr McCue claims! Was your Nan a Nott?? Dazey