According to ancient studies, Cori was protected by concentric walls. Contrary to that, recent studies consider only one defensive wall, the most external one. They believe the other polygonal  walls had a terrace function, to simplify the difficult urbanization, due to the orographical situation, but admitting their defensive character as well.

The three different polygonal manners employed in the walls construction, it is due to different times in their realization. The external one, it’s formed by walls of the first and second manner, considered the oldest (V cent BC, during the Volsci invasions).