Along the busy Autostrada A1, about halfway between Rome and Florence, Orvieto rises like a dreamy apparition — one of those places in Italy you've read about or seen in photos, but whose splendor can only be confirmed in person. Located in west-central Umbria, Orvieto sits — looms, really — on a plateau of volcanic tufa that overlooks the valley formed by the winding Paglia River. Its sheer rock cliffs provided a natural means of defense for the Etruscans — among the pre-Roman tribes who controlled central Italy into the fourth century B.C.E. They lived on "the rock," as Orvieto is known to locals, for centuries before finally capitulating to the Romans, who razed the city.