Road station
Ad Centenarium
Le Boulou
Roman remains on the banks of the Tech, seen by an older scholar at just the right distance below the fortress of Bellegarde, are the best clue to Ad Centenarium, the first station on the Gallic side of the pass. The Roman register of routes calls it Ad Centuriones, at the centurions, and it may have been a customs post. It is placed at Le Boulou, and it was either the same as Aquae Calidae, the hot waters, or close to it. On the map, the start of the stretch to Elne is not marked.