Of all the monuments in France—cathedrals, châteaux, fortresses—the ancient city of Avignon (pronounced ah-veen-yonh) is one of the most dramatic. Wrapped in a crenellated wall punctuated by towers and Gothic slit windows, its old center stands distinct from modern extensions, crowned by the Palais des Papes (Popes’ Palace), a 14th-century fortress-castle that’s nothing short of spectacular. Standing on the Place du Palais under the gaze of the gigantic Virgin that reigns from the cathedral tower, with the palace sprawling to one side, the bishops’ Petit Palais to the other, and the long, low bridge of childhood-song fame stretching over the river ("Sur le pont d’Avignon on y danse tous en rond . . ."), you can beam yourself briefly into the 14th century, so complete is the context, so evocative the setting.

Yet you’ll soon be brought back to the present with a jolt by the skateboarders leaping over the smooth-paved square. Avignon is anything but a museum; it surges with modern ideas and energy and thrives within its ramparts as it did in the heyday of the popes—like those radical church lords, sensual, cultivated, and cosmopolitan, with a taste for lay pleasures. For the French, Avignon is almost synonymous with its theater festival in July—thousands pack the city’s hotels to bursting for the official festival and le Festival OFF, the fringe festival with nearly a thousand shows. If your French isn’t up to a radical take on Molière, look for the English-language productions, or try the circus and mime—there are plenty of shows for children, and street performers abound.