Carcassonne became famous in its role in the Albigensian Crusades, when the city was a stronghold of Occitan Cathars. In August 1209 the crusading army of Simon de Montfort forced its citizens to surrender. Raymond-Roger de Trencavel was imprisoned whilst negotiating his city’s surrender, held in his own dungeon and allowed to die. Montfort was appointed the new viscount. He added to the fortifications. Carcassonne became a border citadel between France and the kingdom of Aragon (Spain).
At the depth of the Promenade of Peyrou in the town of Montpellier stands the chateau d’eau (water tower),a most elegant structure, built by Henri Pitot, ornated by Corinthian columns. Nearby is the eastern end of the 880 m long aqueduct, carrying into the city the waters for the town.