Vienne

If you do nothing but head up to this town's famed Roman Theater and look out over the red-tile roofs of the Rhône Valley, you'll be happy you made the 20-minute trip to Vienne from Lyon. Vienne is a historian's dream, and every street seems to take you to yet another ancient church, another austere Roman ruin, or another postcard-perfect view of crumbling walls and sloped roofs.