Place name origins only have little relation to the Roman names (e.g. Chester - 'Deva', Winchester - 'Venta Belgarum' etc.). Many English places derive part of their name from the river upon which they were built, but in the 16th century many English rivers were renamed with back-formations from towns on their banks. Cambridge, perhaps uniquely, illustrates both effects: originally "Grontabricc", a bridge on the Granta, the name became "Cantebruge" and then "Cambrugge", from which the river was renamed Cam. The vast majority of place names in Wales are Welsh by origin, containing elements such as Llan-, Aber-, Pen- etc. Along the south
New England town the Massachusetts Constitution requires a town to have a population of at least 10,000 people before it can switch its government from a town meeting form to a city form. Nevertheless, even without a hard and fast population limit for city status, the practical threshold to become a city seems to be higher in the three southern New England states than in the three northern New England states. In Massachusetts, Connecticut and Rhode Island, almost every city has at least 10,000 people, and all but a few have at least 20,000. In Maine, New Hampshire and Vermont, however, there are