Palazzo della Ragione, Milan

45°27′53.54″N 9°11′16.16″E / 45.4648722°N 9.1878222°E / 45.4648722; 9.1878222

The Palazzo della Ragione ("Palace of Reason") is a historic building of Milan, Italy, located in Piazza Mercanti, facing the Loggia degli Osii. It was built in the 13th century and originally served as a broletto (i.e., an administrative building) as well as a judicial seat. As it was the second broletto to be built in Milan, it is also known as the Broletto Nuovo ("new broletto").

The palace is decorated with a relief representing Oldrado da Tresseno (podestà of Milan and fierce prosecutor of the Cathar heretics), and the bas relief of the scrofa semilanuta ("half-woolly sow"), which has been object of much controversy among scholars of the foundation and origins of Milan.