From the point of view of the Roman administrator around the year AD 220 Roman Britain contained the same units of urban administration as most of the other provinces of the Empire. The provinces of Britain were divided up into civitates, administrative areas of a size similar to the mediaeval county, or larger, with a town to act as administrative headquarters. These towns are often known as the ‘civitas capitals’ and authority almost certainly had a hand in their genesis because they were planned from the first on the grid-iron pattern which was totally foreign to Britain. London grew, probably by trade, but did not have a civitas around it. At some stage it rose in status, perhaps to a colonia, then to a provincial capital, and finally to be metropolis of the Late Roman group of British Provinces or Diocese. Colchester, Gloucester and Lincoln had military origins but when the army moved on northwards and westwards out of the lowland zone they were fashioned into coloniae, colonies for veteran soldiers. At York a colonia was founded beside the legionary fortress. These, to a visiting imperial official, were the towns of Roman Britain. There is the strong possibility that a few new civitas capitals were later created, and therefore some civitates were subdivided, but this remains uncertain (Frere 1987, 188-98).