Piediluco is a small village on the eponymous lake in southern Umbria, near the cities of Terni and Rieti. 

The name originally derives from a sacred forest that the ancient Roman author Pliny described in his "Naturalis Historia". It was a sacred woodland initially dedicated to the Sabine goddess Vacuna and later, during the time of ancient Rome, to the goddesses Diana and Velinia.

The site was fortified during the Middle Ages, but its heyday came during the conflicts between the opposing factions of Guelphs and Ghibellines. Frederick II of Hohenstaufen gave the castle to the Brancaleoni family, and during the following centuries, it witnessed continuous sieges and struggles between the cities of Rieti, Spoleto, Foligno, and Perugia. Spoleto took the upper hand during the 14th-century, especially during the rule of Cardinal Albornoz.

During the following centuries, the castle was passed on from one local family to another until it was finally abandoned in the 18th-century.

Today, the castle has been partly reconstructed and its two separate parts, the defensive keep and residential quarters, can be clearly distinguished from one another.