Rennes-le-Château is a commune approximately 5 km south of Couiza, in the Aude department in the Occitanie region in Southern France. Thi…Rennes-le-Château is a commune approximately 5 km south of Couiza, in the Aude department in the Occitanie region in Southern France. This hilltop village is known internationally; it receives tens of thousands of visitors per year, drawn by conspiracy theories surrounding a putative buried treasure discovered by its 19th-century priest Bérenger Saunière, the precise nature of which is disputed among those who credit its existence.