7. Historic Rome (Forum, Coliseum, Pantheon, etc.)
8. The other Major basilicas (St. John Lateran, St. Mary Major, and St. Paul Outside the walls).
9. The Holy Stairs (near St. John Lateran) and the relics of the cross in the church of Santa Croce (also near St. John Lateran).
10. Catacombs of St. Callisto or Sebastian (both are nice)
11. Vatican Gardens (reservations here)
12. Borghese museums (reserve here months in advance)
13. The church of Tre Fontane (where St. Paul was martyred)