Roma Termini station is the main railway station of the city of Rome, the largest in Italy (followed by Milano Centrale and Torino Porta Nuova) and the fifth largest in Europe for passenger traffic. It is the only port of call in the historic center of the city, in Piazza dei Cinquecento, and owes its name to the nearby Baths of Diocletian.
With its 32 platforms, it is the largest station in Italy, followed by Bologna Centrale (26 platforms, of which 22 on the surface and 4 underground), Milano Centrale (24 platforms), Napoli Centrale (24 platforms) and Venezia Santa Lucia ( 22).
After the opening of the first two railway lines of the Papal State, the Rome-Frascati in 1856, which stood close to the Aurelian walls at the Porta Maggiore station, and the Rome-Civitavecchia in 1859, then subsequently extended up to Pisa, which had its terminus at the Porta Portese station, and the projects for the Rome-Ceprano and Rome-Ancona lines were already known, the problem arose of giving a set-up to the Rome railway junction and, in particular, of deciding whether to have a single station or one station for each line.
Under pressure from Monsignor de Merode, who had real estate interests in the Via Nazionale area, the first hypothesis prevailed and the Termini area was identified for the new station. This one, located on the Esquiline hill in the Castro Pretorio district, takes its name from the ancient baths of Diocletian, located on the opposite side of the current Piazza dei Cinquecento. In ancient times, the area included rural estates of patrician families. In the sixteenth century, the Montalto-Peretti villa was built there, owned by Cardinal Felice Peretti (later Pope Sisto V), then acquired by the Massimo family, who ceded it to the Papal States when the station was built, and finally demolished. (wiki)