With its different building phases, discovered thanks to renovation in 1964, is both a witness to and symbol of Varese Ligure's importance in the Late Middle Ages.
 
The Fieschi family had originally built a house in the northern part of the Borgo, of which we can now see only the northern wall, now the southern side of the Castle.
 
Two names account for the different building phases: Niccolò Piccinino, a Milanese condottiere, who ordered the construction of the high "offending" tower in 1435; Manfredo Landi, who, having married Antonia Maria Fieschi, built the cylindrical keep with its loopholes between 1472 and 1479.
 
The castle, after the defeat of the Fieschi family by the Dorias, was used for several activities and is now privately owned. It is used for exhibitions and lectures.