This castle is located in the eastern most part of San Terenzo, on a rocky outcrop called La Bastia. It dates back to somewhere between the 10th and 11th centuries and was originally only a watchtower, built to protect the town from barbaric pirate invasions.
Finished in the 15th century, the current day castle is surrounded by a set of defensive walls built on pentagonal foundations. Three round towers with sloping scarp walls are set into the part of the walls that face the keep. Inside the walls lies a second defensive structure in the form of the guardhouse, which was built to guard the main entrance. An imposing square tower, whose battlements are supported by square brackets, dominates the fort.
Although Lerici no longer suffers attacks from the sea, the castle is a positive reminder of the power held by the small commune.