A small gallery of 17th-century paintings housed in a 16th-century palazzo near Campo de' Fiori, with works by Guido Reni, Annibale Carracci, and Jan Brueghel. The main reason to visit is Borromini's Perspective Gallery — a colonnade that appears to be 37 metres long but is actually only 8, using forced perspective and a shrinking floor plan to create the illusion. A marble warrior at the far end appears full-size but is under a metre tall.
One of Rome's more engaging minor sights. Rarely crowded.