Tivoli

Virgil calls it Tibur Superbum in the Aeneid, and the town has kept the epithet: it is still on its coat of arms, beside the imperial eagle granted by Barbarossa in return for its support against Rome. Tivoli claims an origin older than Rome itself, and for a long time it was Rome's rival: its position above the ford of the shepherds' migration was worth too much. Augustus administered justice under the porticoes of the sanctuary of Hercules the Victor, and here, in the third century, Zenobia ended her days, the defeated queen of Palmyra brought to Italy.

Two UNESCO sites in a single comune: Villa Adriana, the palace-city the emperor built himself in the second century by gathering the wonders of the empire, and Villa d'Este, where in the sixteenth century Cardinal Ippolito let loose the most famous water garden in Europe — fifty-one fountains, all gravity-fed, still working. The third wonder is free at first sight: Villa Gregoriana, the romantic gorge where the Aniene plunges, with the old town a hundred and fifty metres above the Roman plain. Rocca Pia was thrown up by Pope Pius II in 1461 to put an end, by fair means or foul, to the town's quarrels. And between 1921 and 1922 Tivoli was one of the last comuni in Italy still run by socialists: part of what was at stake was the electricity of the waterfall, which the town produced for itself.