The Château de Montségur (English: Castle of Montsegur; Languedocien: Castèl de Montsegur) is a former fortress near Montségur, a commune in the Ariège department in southern France. Its ruins are the site of a razed stronghold of the Cathars. The present fortress on the site, though described as one of the "Cathar castles," is actually of a later period. It has been listed as a monument historique by the French Ministry of Culture since 1862.
