The Frontier area of northern England is the most important and reliable source for archaeologists in existence. The perpetuation of the Roman imperial ideal, the survival of classical art and literature, and the spread of the Christian faith depended on the strength of the Empire's frontier and the people who lived there. In Britain these peoples represent nearly 400 years of a cosmopolitan society with the basic elements of a true civilisation. They had greater freedom and security and were more literate and prosperous than at any previous time or for many centuries after. Dr Salway's study of this area is a detailed investigation of the Romanised part of the civilian population to be made. He describes the people themselves and every aspect of their background and way of life, their legal status and their administrative system. He then examines each of the sites individually, making special use of aerial photographs.