In 1258, the Treaty of Corbeil set the border between France and Aragon in the South of the Corbieres region, near the castle. It then became a central stronghold along with five castles strategically placed to defend the French border against the Spanish, under the command of Carcassonne. This is one of the "Five Sons of Carcassonne", along with Queribus, Termes, Aguilar, and Peyrepertuse.
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