The ruins of the Castello di Gennaro allow one to recognize at least three important historical moments that reconstruct the history of the towns of central Italy. The first building dates back to the Roman Republic period, IV - III century BC, with square tuff blocks. Then the area became an imperial villa in the first century AD and the remains of a cistern of the bath are seen. The third is the transformation into a castle in the twelfth century AD, witnessed by the city walls and the remains of the towers. The construction of the fortified walls by the Annibaldi family did not last long and in 1303 the Velletri destroyed it. The area has always been rich in history and many remains have been found. It is interesting that a concession for excavation of antiquities was granted on October 10, 1563 and renewed on 2nd March of 1575 to the benefit of Andrea of Velletri.