The Cité of Carcassonne is a medieval city which was added to the UNESCO list of World Heritage Sites in 1997. It was first settled in the 5th Century BC by the Gauls, then fitted with ramparts in the 4th and 5th century A.D. In the 12th century A.D., the vicomtes Trencavel built the castle within the walled city. In the 13th century, the cité was annexed by the King of France during one of the crusades. More fortification of the outside ramparts followed in later centuries.
It fell into neglect in the 16oo's. Luckily, architect Eugène Viollet-le-Duc recognized the importance of this walled city and began a thorough restoration in the 1800s.