Taking a train is simply the best way to travel around Italy as it has a highly-developed high-speed rail network that connects all major cities and slower local trains that connect most of the small towns.
Driving and parking in Italian cities is a nightmare and the new high-speed train network is now faster, more convenient and more relaxing than flying. Train is great and fast option if you need to reach cities withing Italy. For example, you can travel from Rome to Naples in only 1 hour, to Florence in 1.5 hours or to Venice in 4 hours.
Trenitalia is Italy's national train operator, which operates the most train routes in Italy. Le Frecce high-speed trains include Frecciarossa, Frecciargento and Frecciabianca.
Le Frecce trains feature smoke-free, air-conditioned car where travelers enjoy spacious seats. Frecciarossa and Frecciargento trains offer speedy service to cities that include Rome, Florence, Venice, Milan, Bologna and Naples with direct access to the city centers. Frecciarosa are the fastest trains with great service. In business class they offer comfortable and clean seats with lots of room. They offer you some snacks and drinks and newspapers.
Frecciabianca offer traditional service and convenient access to an assortment of smaller Italian towns and destinations.
InterCity are relatively fast trains (100 - 125 mph) that run along Italy, stopping at cities and large towns. There are first and second class service available at these trains. First class coaches offer slightly better seats and generally less crowded.
Regionale Veloce trains connects smaller cities and operate all over Italy. Fares for these trains are very cheap. No seat reservation is necessary. Luggage goes on the rack or if necessary on the floor.
Private operator, Italo Treno operates trains on the Milan - Bologna - Florence - Rome - Naples route and Venice - Florence - Rome route. For times, fares and online booking check their official web site. Italo trains have four classes (Smart, Comfort, Prima and Club), all with free Wi-Fi and leather seats.
Train tickets can be purchased from any train station - either from a ticket counter or an automated machine. You can also buy tickets in advance from several web sites. Here are some of them.
Rail Europe is the official North American distributor of Italian rail tickets and it is user-friendly
ItaliaRail is a worldwide distributor of Italian train tickets so their site is simple to use for English speakers. You can use a credit card to pay in most currencies so anyone in the world can buy through this web site.
Trenitalia is the official Italian railways website. The website is easy to use and you can easily book your train tickets through this web site.
Italotreno is a private rail company that runs modern high-speed trains between most major cities - these trains only run between major cities.
TrainLine.com: TrainLine is a website that searches multiple rail services across Europe so it's great for international trips. It's also good for single country travel. It is designed for English-speaking travellers so it's super user-friendly.
Tickets for Le Frecce trains always include a seat reservation and are only valid on the specific date and train you've booked.
On high-speed trains your tickets is only good for the time and date on the ticket. You will have also an assigned seat. You ticket will show the car and seat number so make sure you're on the right car.
On regional trains you will probably have a paper tickets which you need to validate in the validation boxes on the platform before you get on the train. If you bought your ticket online you will have to show to the conductor when he comes to check the tickets. Regional trains don't have seat reservations so just sit anywhere you like.