Coming from the Lower Valley, the first ancient monument in Aosta to welcome visitors is the Roman bridge that sits above the ancient course of the Buthier River. It characterises the eastern quarter of the city, called Pont de Pierre, that is, “bridge of stone”. Parallel to Corso Ivrea, a short distance from the Arch of Augustus, the bridge is perfectly preserved and is still used as a thoroughfare today, although the Buthier River changed its course during the Middle Ages and the waters no longer flow under the single humpback arch with its 17.16 m span. Approximately 6 m wide, it was built during the Augustan age with blocks of stone, in compliance with the customary Roman models of the time.