As every “fuori sede” does (literally translated from “out of location”, referring to all those students that have to leave their hometowns to study elsewhere) I know a lot about travelling around Italy. I changed universities and moved to different cities within Italy in the past two years, and having family and friends spread around the country, has only increased my knowledge on the transport system in Italy.
Starting with trains, we have two main railway companies: Trenitalia and Italo. Along with them, you may find other companies such as Thello, ÖBB (Österreichische Bundesbahnen) and DB (Deutsche Bahn) that link Italy with France, Austria and Germany respectively.
Trenitalia is in charge of both regional (slow trains that connect small towns to big cities) and high-speed trains (connecting only big cities); prices vary on the distance traveled, on the service (first, business or second class), and on the speed of the train (general rule: the slower the cheaper). It is the main railway company in Italy and can take you almost everywhere in the country. If you are younger than 26 and have an Italian ID or passport I recommend you subscribe for “cartafreccia young”, which can give you up to 50% discounts on high-speed trains. I suggest you book your tickets as soon as possible to save up.
Italo is the underdog, the newly born company that competes with Trenitalia for high-speed connections. Unlike Trenitalia, it is not present in every single station but only in the largest cities. Its services are very nice but the best thing of all is the affordable first class deals; sometimes Italo’s first class may cost you less than second class if you don’t mind not having cancellation options on your ticket. If you are travelling with Italo it is extremely important to book in advance as prices skyrocket very quickly.
In my opinion, trains are the key to visiting most places in Italy and are also perfect for one-day trips. Leaving early in the morning to come back at night will allow you to spend a full day in any city around you.
If you don’t mind spending a few more hours in order to spend less, many bus companies will take you anywhere in the country. For short trips buses might be much more convenient than trains and can take you to small towns that would be otherwise unreachable by train; however if you are planning on visiting a distant town, keep in mind that buses do take a long time to travel from city to city and traffic on highways also slows them down. The most popular bus company is Flixbus, but there’s plenty of others which you can simply google search, or go to your closest train station to learn which companies service your area.
I only recommend taking a plane if you are going to Sicily and Sardinia (Italy’s major islands), but there are also many ferries companies that will take you to both of them as well as to the minor islands from the mainland.