Flight Don Mueang International Airport departs from Bangkok Don Mueang International Airport at 16:00 and arrives at Riyadh King Khaled International Airport at 20:20.
The flighttime is about 8h 20m. The distance travelled ("as the bird flies"): 5975 Km. So the average speed is roughly 717 Km.
There is an 4 hour time difference between Bangkok and Riyadh
