A village in the province of Viterbo that stands on a tuffaceous cliff between the Volsini Mountains whose name derives from a number of caves of which the surrounding area is particularly rich and which constituted the first dwellings of the inhabitants who fled from the hill of Civita following Longobard raids. Grotte di Castro tells of its Etruscan roots and its role in the Middle Ages as a possession of the Church. The different souls of the town, in fact, gave birth to one of the most interesting centers among those found near Lake Bolsena.