The Cusani Visconti Castle, or Chignolo Po Castle, was built in the 13th century on a Lombard stronghold, of which only the Tower remains, built by King Liutprand in 740 to control the Po and the Via Francigena. The fortress is, in fact, remembered by Sigeric as stage XL of his return journey. In the 13th century, the castle became one of the major Lombard fiefdoms and its ownership passed first to the Pusterla and then to the Cusani. Thanks to the latter, in particular Cardinal Agostino Cusani Visconti, in the 18th century the structure changed from a defensive stronghold to a princely palace. Architect Giovanni Ruggeri added the large park, the elegant Baroque building known as the ‘Palazzo del Tè’, the courtyard of honour and the east wing. The latter houses rooms richly decorated with stucco and frescoes, as well as flats where important names such as Napoleon Bonaparte, Francis I of Austria and Pope Clement XI stayed. Today, the castle also includes the Museum of the History of Lombardy’s Agricultural Civilisation and the Lombard Wine Museum.