This keep with bossed walls was built on the ruins of a Gallo-Roman rampart that used to defend the city centre in ancient times. Built in the late 13C, it was a testament to episcopal power in the face of the viscounts housed on the other side of the square. From the walkway of its platform (142 steps), the view stretches over Narbonne and its cathedral, the surrounding plains, Clape mountain, the marshland and the Pyrenees in the distance.