Rome takes first place because it combines incredible attractions with excellent railway connections. Roma Termini connects the Italian capital with almost every major city in the country. Once you arrive, ancient history is everywhere. Visit the Colosseum, the Roman Forum, the Pantheon, the Trevi Fountain, the Spanish Steps, and Vatican City.
You could easily spend several days exploring and still have more to see. For anyone planning to discover Italy by Train, Rome is an essential stop.