The Loire Valley is known for its rolling green countryside, its distinctive wine and probably most of all for its magnificent castles. The most stunning of all these great structures is the Château de Chenonceau perched (literally) on the River Cher not far from the town of Amboise. It was built in the 16th century and has been home to several leading ladies of France, most notably Diane de Poitiers and the queens Catherine de Medici and Louise of Lorraine. Inside, you wander through a succession of drawing rooms, bedrooms, kitchens, galleries and great halls, all filled with priceless paintings, tapestries and other furnishings. Outside, you are treated to the elaborate 12,000-square-meter garden created by Diane and the more "intimate" 550-square-meter garden created by Catherine. As open houses go, this one is in class by itself.