Marvellous basilica situated on Via del Corso 437 which hides in it's interior St. Charles' Hearth Relic (behind the major altar).

The Basilica Dei SS Ambrogio E Carlo has free entrance and sure is worth the visit. It was the first site I entered in Rome because it was right beside the hotel . Nevertheless none of the several churches you have to choose from in Rome comes short of it.

Make sure you appreciate the marble columns and the ceiling paintings near the altar that seem to carry the weight of the church under their backs.

More information can be found here . It's in italian though.