The Castra had an imposing square defensive wall, with embattlements on the top, and its rectangular plan measured 435 metres in length by 232 metres in width, covering an overall surface of 10 hectares. The defensive structure was completed with a series of circular towers in the corners and square based ones along the sides.

At present one can still see stretches of the walls, a number of the towers and extensive remains of buildings, the most important entrance gates, a few segments of the paved road and urban structures as well as the ruins of civil buildings such as warehouses and dwellings.