Air distance from Ulaanbaatar, Mongolia to Athens, Greece is 4062.7 Miles (6538.2 Kilometers / 3528 Nautical Miles).
8 hrs, 26 mins is the flight duration between Ulaanbaatar and Athens. This is the In-The-Air flight time. You should also add the taxi time, airport wait times and possible delays due to bad weather, etc. for the total flight duration time.