Built in 1450-66 by Francesco Sforza, as both fortress and residence, in the place where the Visconti stronghold once stood (1358-68), the Castle of Milan presents itself in its restored state, as restored and saved from demolition by Beltrami.

The imposing Filarete tower, which was demolished by lightening and rebuilt at the turn of the 19th Century is his work.

The remains of ancient constructions can be seen in the famous Piazza d'Armi.
Other two towers characterise the structure: the Bona di Savoia Tower and the Rocchetta Tower, in which the Lords of the castle took shelter in times of peril and now home to the 'sala del tesoro' (treasure hall), where the "Argo" painting by Bramante is displayed.

Restructured in the post-war years, the Castle is today host to the Civic Collections of Ancient Art (sculpture, with Michelangelo's "Rondanini Pietà ", a picture gallery and art room), of applied Art and engravings with ceramics, ivories, bronzes, tapestries, musical instruments and "Bertrelli" prints), of Archaeological (Egyptian and pre-historic sections) and numismatic art and to the Trivulziana Library.