Flight Athens International Airport Eleftherios Venizelos departs from Athens Athens International Airport Eleftherios Venizelos at 13:20 and arrives at Belgrade Belgrade Nikola Tesla Airport at 13:55.
The flighttime is about 3h 35m. The distance travelled ("as the bird flies"): 816 Km. So the average speed is roughly 228 Km.
There is an 3 hour time difference between Athens and Belgrade