The Château Comtal (Count’s Castle) is a medieval castle within the Cité of Carcassonne, the largest city in Europe with its city walls still intact. The Medieval Cité lies within the modern city of Carcassonne in the Aude department, of which Carcassonne is the prefecture, in the former province of Languedoc.  Although the outer curtain wall of the cité is French, and the whole site has been substantially restored, the Château Comtal has a strong claim to be called a "Cathar Castle". When the Catholic Crusader army arrived in 1209 they first attackedRaymond-Roger Trencavel's castrum at Bèziers and then moved on to his main stronghold at Carcassonne.

The castle was restored in 1853 by the architect Eugène Viollet-le-Duc. It was added to the UNESCO list of World Heritage Sites in 1997. You can visit the medieval city (free) and the Château Comtal (entry fee).

Carcassonne was besieged from 1st to 15th of August 1209 during the early phase of the War against the  Cathars of the Languedoc. The siege followed soon after the Crusaders' massacre of the entire population of Béziers, an act of terror designed to terrify the people of the area. Raymond-Roger Trencavel was Viscount of Béziers as well as Carcassonne - his cities were deliberately targeted by the Crusaders, as the Count of Toulouse had joined the Crusade himself, gaining immunity for his own lands.