Throughout the 13th century, Carcassonne is regularly threatened. Louis IX orders the construction of a second enclosure to improve its defenses. Much later, in 1853, Napoleon III decides to undertake restoration work on the medieval city of Carcassonne. They are directed by the architect Eugène Viollet-le-Duc and receive numerous criticisms. The roofs are indeed redone in a conical form with slates, while those of the surrounding castles are more often flat and covered with Roman tiles.