The strongholds were built beginning from the fourth century to provide protection in the strategic points of the area and to protect the local populations, caught between the fighting of the different factions, the constant raids by bands of thieves and the attacks from ferocious animals such as wolves and bears, present in great numbers in the Apennines at the time. The walls of these massive square constructions were typically over a metre thick, and the stables and equipment storehouses were located on the ground floor. The upper floors meanwhile, connected to the ground floor by a hanging ladder taken inside during the night, were used for storing provisions and the precious seeds. Two centuries later, when the Estense dominion became established in the area leading to a reduction in the need for defences, the strongholds were transformed into houses with towers, often used as the master's residence.