Does this seem doable?
8 am- Leave for Appian Way (half day)
Saint Callixtus Catacombs
3:00 pm- Borghese Gallery
Walk down Janiculum Hill to Trastevere (see St. Pietro in Montorio if possible)
Dinner in Trastevere
We are staying a few blocks from the Vatican. We plan to leave the appian way by 12 as everything will be closing up for lunch.
Thanks in advance for any help you can offer!