Santa Maria della Pace is a small but rewarding church near Piazza Navona, best known for Raphael's fresco of the sibyls in the Chigi Chapel. Bramante's cloister next door gives the complex another layer of Renaissance interest.
It is easy to miss among the busier sights around the Pantheon and Campo de' Fiori. Step inside if it is open; the visit is short, quiet, and unusually rich for such a tucked-away church.