Chester

Chester takes 1 day to see: the Roman and medieval city wall, complete and fully walkable, in a morning walk, and the Rows, unique two-tier medieval shopping galleries found nowhere else in England, in the afternoon. April-October is best. It's mid-priced by British standards. It was founded by the Romans as a legionary fortress, and its wall -the most complete of any English city- allows a circular walk of nearly 3 kilometers without ever stepping down to street level.