Flight Leonardo da Vinci–Fiumicino Airport departs from Rome Leonardo da Vinci–Fiumicino Airport at 11:20 and arrives at Istanbul Istanbul Atatürk Airport at 16:00.
The flighttime is about 3h 40m. The distance travelled ("as the bird flies"): 1844 Km. So the average speed is roughly 503 Km.
There is an 1 hour time difference between Rome and Istanbul