The Palazzo Bonacolsi, also known as Palazzo Castiglioni, is a 13th-century Gothic-style aristocratic palace located in the center of the town in Piazza Sordello in front of the Ducal Palace in Mantua, region of Lombardy, Italy.
Most of the members were traditionally based in Milan: the Mantuan branch originated in 1440 from Baldassarre Castiglione the elder, the grandfather of author of the Libro del Cortigiano.
The palace was built in the late thirteenth century by the Pinamonte Bonacolsi on land purchased from Rolandino de Pacis.
Pinamonte also bought adjacent palaces and buildings in civitas vetus, including the tower of the cage, symbol of the power of Bonacolsi.
The most prestigious palace was left by his father to his second son Bardellone, his successor as leader of the city.