Yes, you can certainly find taxis in Rome at 4:00 AM, but the strategy for getting one differs from the daytime "hail-on-the-street" approach. In the early morning hours, it is best to go to an official taxi stand (identified by a "TAXI" sign on a burnt-orange or white pillar), which are located near major hubs like Termini Station, Piazza Venezia, or Largo Argentina. However, for a guaranteed pickup at a specific time—especially for a flight from Fiumicino or Ciampino—it is highly recommended to pre-book using an app like Free Now (formerly MyTaxi) or itTaxi. These apps allow you to schedule a ride in advance and track your driver's arrival. Alternatively, you can have your hotel concierge call a radio taxi for you. Be aware that Roman taxis are required by law to be white with a "TAXI" sign on the roof and a license number on the door; avoid any "private" drivers offering rides inside the airport or near stations. At 4:00 AM, a "night supplement" fee is automatically added to the meter, but for trips to the airports, there are fixed government-regulated fares (e.g., 55 Euro to Fiumicino from within the Aurelian Walls). Pre-booking ensures that you don't find yourself stranded on a quiet cobblestone street while trying to catch an early flight.