Pompeii gives you a genuine feel for life almost two thousand years ago. You also normally need to pass through Naples to get there. This southern Italian city has spots that are gorgeous and spots that make you feel like you walked onto the set of the Godfather. There is an expression that in Milan (in the north of Italy), traffic lights are traffic lights, in Rome (the centre of Italy), they are suggestions, and in Naples, they are Christmas decorations. You definitely feel this going around Naples.
Recommendations from Barbara
You can do Pompeii as a day trip from Rome, but I recommend staying a night in Naples.
Naples is famous for (not surprisingly) Neopolitana pizza. It’s fairly different than the pizza you find even a bit more north in Italy.