Leonardo Express

1. Get cash. If you don't have any euros, we'd suggest withdrawing cash from a bancomat or ATM in the terminal.

2. Go to the airport's railroad station. In the corridor outside baggage claim, look for blue overhead signs that show trains and other forms of transportation. 

Follow the train signs, which will lead you (via escalators and an elevated tunnel) to the Stazione Ferroviaria or railroad station, which is in the same direction as the parking garages and the Hilton airport hotel.

3. Buy a ticket. You can purchase biglietti from the green Trenitalia ticket machines, at the biglietteria or ticket counter, or--even more conveniently--at the newsstand/tobacconist in the station (shown above).

The ticket machines and the railroad's ticket counter accept credit cards; at the newsstand, where customers are likely to be in a hurry, we'd suggest paying the €14 fare in cash.

If you prefer, you can order e-tickets online, though you'll need to register with the Trenitalia Web site to use this option. (Two types of e-ticketing are available: PDF files that you print, and paperless tickets for your smartphone.)

4. Validate your ticket. Be sure to validate your ticket by inserting it in one of the machines on or near the platforms. If you're caught riding the train with an unvalidated ticket, you can be slapped with a fine of €50 (payable on the spot) plus the standard fare.

• Exception: E-tickets purchased online needn't be validated.

5. Board the train. The Leonardo Express is a single-level train with a distinctive livery and the name "Leonardo Express" painted on the cars. All carriages are first class, so you can board by any door. (If the door is closed, press the round button to open it.)

6. Enjoy the ride. The Leonardo Express departs from the airport at 5 or 35 minutes past the hour. It won't stop until you reach Termini Station, 31 minutes after leaving the airport.

When you exit the train, remember to take everything with you--including any bags that you may have placed under or between the seats, in the overhead rack, or in the baggage area at the end of the car.

The Leonardo Express arrives near the back of Stazione Termini, so you'll need to walk five or ten minutes to the front of the station to find the Metro, buses, and taxis.

1. Buy a ticket. Tickets are available at Terminia's biglietteria or ticket office (where the lines are often long), at independent vendors such as travel agencies and newsstands, from Trenitalia's multilingual touch-screen "Biglietto Veloce" ("Fast Ticket") machines, or online.

You can also buy your ticket from a desk near the trains, but you'll pay an extra euro for the convenience, and you may have to wait in line behind other tourists who didn't plan ahead. (Don't risk this in the early morning or late at night, when the "Controllo Biglietti" or "Ticket Check" desk may be unmanned.)

2. Go to the Leonardo Express platforms. Follow the overhead signs that read "Terminal Fiumicino Aeroporto," which will lead you to Tracks 23-24 near the back of the station on the right-hand side as you enter from the front. It's a long walk, so allow 5-10 minutes to reach the trains.

When you reach the "Biglietto Controllo" or "Ticket Check" desk, you should see a Leonardo Express train waiting by the platform. (You can show your ticket to the agent if you wish, but you aren't required to do so--the  agent is there mostly to sell tickets to tourists who arrive unprepared.)

3. Validate your ticket. Look for a small machine just beyond the "Biglietto Controllo" or "Ticket Check" desk.

Do not forget this step! If you ride the train with an unvalidated ticket, you're subject to a fine of €50 plus the price of the ticket.

4. Board the train. The Leonardo Express is a one-class train without seat reservations, so you can sit in any car. (Keep your ticket handy--the conductor will check it during your journey.)

Travel time to the airport will be 32 minutes. (Trains leave at 15- to 30-minute intervals from early morning until late at night.)

5. At Fiumicino Airport, look for the departures monitors. After leaving the train, walk to the tunnel just beyond the station.

You'll see a bank of vertical computer monitors that list "Partenze/Departures." Next to each departure is the number of the terminal where passengers need to check in. Identify your terminal, then follow the overhead signs to reach T1, T2, or T3.

Cheaper trains and other Rome stations:

ABOVE: A commuter train at Fiumicino waits for passengers to Trastevere, Ostiense, Tiburtina, Termini, and other stations in Rome.

About the author:

Durant Imboden is a professional travel writer, book author, and editor who focuses on European cities and transportation.

After 4-1/2 years of covering European travel topics for About.com, Durant and Cheryl Imboden co-founded Europe for Visitors (including Rome for Visitors) in 2001. The site has earned "Best of the Web" honors from Forbes and The Washington Post.

For more information, see About Europe for Visitors, press clippings, and reader testimonials.