Flight Heathrow Airport departs from London Heathrow Airport at 18:20 and arrives at Rome Leonardo da Vinci–Fiumicino Airport at 21:55. The flighttime is about 2h 35m. The distance travelled ("as the bird flies"): 1771 Km. So the average speed is roughly 686 Km. There is an 1 hour time difference between London and Rome
