Glevum was established around AD 48 at an important crossing of the River Severn and near to the Fosse Way, the early front line after the Roman invasion of Britain. Initially, a Roman fort was established at present-day Kingsholm. Twenty years later, a larger legionary fortress was built on slightly higher ground nearby, centred on present-day Gloucester Cross, and a civilian settlement grew around it. Probably the Roman Legion XX Valeria Victrix was based here until 66 and then Legio II Augusta as they prepared to invade Roman Wales between 66 and 74 AD, who stayed later until around 87.