It’s said that in his old age Bernini liked to come to enjoy the peace of this 17th-century church, regarded as among his greatest architectural feats; though small, it has an uplifting intensity. Look for the cherubim looking down on worshippers from the lantern and altar. It was also a favorite of Pope Alexander VII, who used it while residing at the Palazzo del Quirinale.
You can also visit the three rooms where St Stanislaus Kostka (€2) spent his last weeks before dying aged 17 in 1568. After experiencing a vision he had walked from Vienna to Rome, and is the patron saint of youth.