In the Aude <i> Department</i> in south west France. Carcassonne has a very long history; there were Celtic and Roman forts on the site long before the Visigoths founded the city in the 5th century. It was an important city throughout the middle ages and was beseiged by de Montfort during the Albigensian Crusades in the 13th century. The old part of the city, on the higher ground, still retains its medieval character today , at least on the outside; it's very much geared up for the tourists inside.