Ravenna is on the tourist map for one reason: its 1,500-year-old churches, decorated with best-in-the-West Byzantine mosaics. The city's churches and mosaics date from the time (c. AD 400–600) when it was the center of Western civilization — a civilization in transition, from Roman to barbarian to Byzantine to medieval. Ravenna has a delightful workaday quality, providing relief from the touristic intensity of Venice and Florence. Residents go about their business, while busloads of tourists slip quietly in and out of town for the best look at the glories of Byzantium this side of Istanbul — specifically, the richest collection anywhere of mosaics from the fifth and sixth centuries. Many are pleasantly surprised by the peaceful charm of this low-key town. If it seems less prettied-up than some of the more famous Italian towns, well…that's sort of the point.