The concept of a legionary fortress as a permanent structure dates from the reign of Augustus (27 BC-AD 14). It is only from that time that we find a standing army distributed around the empire, and their permanent fortresses developed from the temporary field fortifications of the legions on campaign. This book describes the development, design and construction of these fortresses throughout the length and breadth of the Empire. It also deals extensively with the experience of life within a typical fortress and covers the operational history of these fortifications, including the famous siege of Vetera in AD 69.