Château de Pierrefonds (Oise), built between 1396 and 1407 by Louis d'Orléans to control the route between Flanders and Burgundy, and at the request of Emperor Napoléon III restored by Eugène Viollet-le-Duc starting in 1858, who reconstructed the castle art of the late fourteenth century for the exterior, and conceived an imaginative neo-medieval residence for the interior. ©Photo J.-Y. Andrieux.