In the 3rd century BC, the historian Polybius described Akragas as an ingeniously fortified city.
In order to defend themselves against possible enemy attacks, the Agrigentine people had built a mighty wall 12 km long, which made the most of irregularities in the terrain.
Construction of the first walls dates back to the end of the 6th century BC, when the city was fortified on each side of the plateau where it stood, though traces of additions, modifications and renovations were found in later centuries.
The original project envisaged perfectly square stone blocks arranged using the isodomic technique.
Access to the city was granted through Porta Scea gates , including the Porta V , on the southern stretch of the walls, which is the best preserved.
The gates were placed at different heights and depths, but always corresponding to small valleys or slight depressions so as to follow the original lay of the land and take full advantage of an arrangement that may have proved to be a natural protection in itself.
On the east side were Porte I, II, and III; to the south, Porte IV and V; to the west, Porte VI and VII; and Porte VIII and IX on the north-west side.
Some hypotheses also place a Porta X to the north, but there are no traces to confirm this.