The fortress imposes itself on the Colle Albano with its 900 meters of walls, punctuated by 15 square towers. In the material and chromatic order dictated by the brick of the walls creep to the eastern and southern ends of the interruptions, consisting of the only two circular towers of the complex: the tower of the Queen (or Lioness) and that of the King (or Leo). Both cylindrical and in white limestone. The southern tower, that of the Queen, is larger than the other and has more architectural and decorative definitions. With a circular base and cylindrical development, the tower is 25 meters high and has a base with 14 wide rusticated cladding. The tower is a kind of keep and its shape and position remind French models like that of Cloucy, destroyed during the First World War.
The structure is equipped with three loopholes for archers, and is characterized by a beautiful crenellation. The tower of garrison and defense was equipped with a system that allowed, in case of siege, to make raindrops on the assailants. It is certainly the best preserved element of the Fortress and you can access its interior; from it you can also reach the walkways above the walls of the fortress and admire the beautiful panorama that stretches from the "Piana di Puglia" to the Monti Dauni.