Fiumicino-Leonardo da Vinci Airport

Rome's major scheduled airline handler
Word to the wise: Leonardo Express is the fastest route into the city centre.
Fiumicino has three passenger terminals - Terminal A handles domestic flights, Terminal B some domestic and international flights, and Terminal C is responsible for transatlantic carriers. Airport information kiosks with user-friendly touch-screen technology are free to use in Terminal A.

The airport is easily accessible by train, and the Leonardo Express takes roughly 30 minutes from Termini - Rome's central train station - for a ticket price of EUR 14, departing from Track 24. Passengers are advised that the ticket expires after 75 minutes, and must be validated at the yellow validation machines before travel.
Similarly the Sabina-Fiumicino line (FR1) also goes to the airport (EUR 8). This connects to the Rome Metro via Tiburtina Station or Ostiense Station, but does not travel directly via Termini.