A large fortress that served as the grand palace of Galeazzo Visconti II. Its construction began in 1360, and its original purpose was as a palace for leisure and entertainment. While the architecture was designed as a defensive fortress—evident from its towers, moat, and bridge—the interior spaces are adorned with frescoes, indicating that it indeed functioned as a reception palace. Today, it houses the Civic Museums, which include archaeological finds and a collection of 18th-century paintings.