Built between 1470 and 1476 as a mausoleum for the condottiere Bartolomeo Colleoni, this chapel is one of the finest examples of Lombard Renaissance architecture in existence. The facade is a riot of coloured marble — red, white, and green — carved with reliefs, statues, and ornamental medallions in a style that has no parallel in northern Italy.
The interior holds the sarcophagus of Colleoni himself, elevated on a plinth under an equestrian statue gilded in gold, and that of his daughter Medea. Tiepolo painted the ceiling fresco — a late addition that sits oddly with the 15th-century stonework but is worth looking up for anyway. The chapel is free to enter and sits directly behind the Basilica di Santa Maria Maggiore on Piazza del Duomo. It is consistently overlooked by visitors who spend all their time in the basilica next door.