Ferentino (Antino in past times) is located on a hill above the Sacco River valley, in a strategic position between Lazio, Campania, and the Tyrrhenian and Adriatic Seas. This position made it a loyal ally of Rome, along with its imposing walls.

The megalithic walls of Ferentino extend for over 2500 meters (8202 feet) and are characterized by polygonal stones without mortar.