We have been in Rome since Sunday. We’ve walked and toured major highlights. We are day tripping to Florence. We have one day on Thursday we need to fill. We leave Friday unless we stayed til Saturday. We are thinking of taking a day trip to Naples. Depending on flights we would be leaving Friday anywhere from 1030-2:00 PM.
Suggestions for Thursday in Naples or find something closer to Rome to fill the day.
Have you been to Ostia Antica - an ancient Roman city just outside Rome and the original port of Rome, although now inland.
There's a train service.
https://www.rometoolkit.com/whattodo/ostia_antica.html#getting
Orvieto would make a good day trip. The regional train ride is under an hour. https://www.ricksteves.com/watch-read-listen/read/articles/orvieto-what-an-italian-hill-town-should-be
Re. Orvieto suggestion. The city is fantastic. However, we expected to get to Orvieto from Rome in about an hour. It took us about half a day. Maybe things change in summer, because we were there in February. When we arrived Termini, we had to wait 2 hours for a train to Orvieto. Then there was a connection where we had to switch to a bus. When you arrive Orvieto train station, you need to take a funnicular and then either walk 3/4 mile to city center or take a bus.
Incidentally, we've been in Rome over two trips, for 12 days. There is so much yet that we'd like to see in Rome.
Have you been to the Appian Way? We did a golf cart tour and saw some catacombs and other ruins. It was really fun.
Have you done a food tour? Also, one of my favorite things to do in Rome www.eatingeurope.com
Have you been up to the top of Castel SantAngelo? Great view!
Look at Tivoli - the gardens and fountains at Villa d'Este and the ruins at Hadrian's Villa.