The Arengario is the medieval civic building that dominates the main square of Monza, a handsome 13th-century structure combining Romanesque and early Gothic elements into a well-proportioned whole. The ground-floor arcade — originally open on all sides — served as the covered public forum of the medieval commune, while the upper floor housed the administrative offices. The corner towers and crenellated parapet give it the martial seriousness typical of northern Italian civic architecture of the period.
The building now houses the Musei Civici di Monza, which includes a collection of paintings by local and regional artists — modest in scope but strong on works from the 19th-century Lombard school, including pieces by Mosè Bianchi, whose bronze monument stands in the adjacent square. The Arengario faces the cathedral across a pedestrianised square that forms the heart of the historic centre; the two buildings, civic and religious, frame the central space of medieval Monza much as their builders intended.