Question: what is the difference between roma termini to rome tiburtina?
Answer: Tiburtina isn't really on the "outskirts", its in the city about a mile northeast of Termini. It is a through station, not a terminal station, so the trains there just stop for a few minutes and then keep going. It is also the only place for Italo high speed trains. It is 4 Metro stops away from Termini.