The largest train operator in Italy is Trenitalia, which is a division of the Italian government. The company has been in existence since 1905, and the train network throughout Italy has been steadily growing and improving—it's by far the easiest and most cost-effective way to get around the country.
The fastest trains operated by Trenitalia are the Alta Velocità (AV) series, called in descending order of speed: the Frecciarossa (“Red Arrow”); Frecciargente (“Silver Arrow”); and Frecciabianca (“White Arrow”). These only connect a short list of Italian cities, however—Turin, Milan, Bologna, Florence, Rome, Naples, and Salerno. The Frecciarossa trains can reach speeds of up to 190 MPH (300 km/h). Reservations are required on AV trains.
InterCity trains are the next-fastest option, running at up to 125 MPH (200 km/h), and connecting mid-sized cities and towns across long distances, as well as the biggest cities served by the AV trains. Reservations are also required on InterCity trains.
The slowest Trenitalia trains fall under the category of “regional” trains, and go by names like “Regionale,” “Diretto,” and “Espresso.” These are intended to serve every last small town with a train station, and they typically stop at every single station between two larger cities. If you're in a hurry, this isn't the best news, but if you're headed to a more remote part of Italy, this may be your only option.
TrenItalia manages the railway systems in Italy, together with few other private railway companies. The rail network is well developed and widespread, especially between major urban centres and tourist areas. The fastest services operate between the major cities, while all other services (Espresso, Regionale) connects the smallest towns, and even if much slower they are affordable and reliable.
Train types and classification
Alta Velocità (formerly known as Eurostar Italia) - The cream of the Italian trains, these are services running at high speed connecting all major Italian cities. Some of these services are making use of the newly opened High Speed tracks, operational on the new Turin - Milan - Bologna - Florence - Rome - Napoli lined since the beginning of 2010. Reservation is always compulsory, and services include 1st and 2nd class travel, air conditioned coaches, soundproofed music, mini-bar service and/or restaurant car. Passengers travelling in 1st class coaches get a welcome drink and a small snack on boarding the train, the newspaper of choice and have exclusive access to the Club Lounge at the station.
Intercity - Comfortable and fast services connecting main cities and towns. Services include 1st and 2nd class seating, air-conditioned and no compulsory reservation requirement; however for passengers wishing to secure their seats in advance this can be done right here on this site, or at any Italian station, for a minimal extra charge.
IntercityPlus - Modernized & refitted services, with more comfortable seats than regular IC, sockets for laptops in 1st class and better designed tables, connecting main cities and towns. Services include 1st and 2nd class seating, air-conditioned coaches, mini-bar and restaurant car. The compulsory seat reservation requirement is included in the ticket price at the time of purchase.
Eurocity - Intercity day services when in Italy, these are effectively trains coming from bordering countries connecting main cities across Europe. They might not be run by Trenitalia, and they do not require a compulsory reservation once in Italy.
IntercityNight - Intercity services travelling long distances overnight across Italy, they carry comfortable sleeper accommodations, from a couchette (bunk bed) in a 6-berth compartment to the new ‘comfort’ 4-berth compartments; from double and single sleeper cabins, with proper beds and washbasin with hot and cold water.
Espresso - Usually travelling long distances overnight, mostly 2nd class only with couchettes and sleepers available.
Regionale - Local services stopping everywhere, they can take you to the most rural location and most of them have 2nd class coaches only.