Aquileia

This sleepy little town was, in the time of Emperor Augustus, Italy's fourth most important city (after Rome, Milan, and Capua). It was the principal northern Adriatic port of Italy and the beginning of Roman routes north. Its prominence continued into the Christian era. The patriarchate (bishopric) of Aquileia was founded here around 314, just after the Edict of Milan halted the persecution of Christians and about the time that the Emperor Constantine officially declared his conversion. After several centuries of decline and frequent pillaging, including a sacking by Attila the Hun in 452, the town regained its stature in the 11th century, which it held onto until the end of the 14th century. Aquileia's Roman and early Christian remains offer an image of the transition from pagan to Christian Rome. Aquileia is also refreshingly free of the mass tourism that you might expect at such a culturally historic place.