That depends on where you depart.
with stopover at London 6 hours
A direct flight shouldn't take more than 3-4 hrs.
If it is a chartered direct flight between abardeen and Sofia/Burgas or Varna then it will take 3 hour 54 minutes, Stopovers will add more time
By direct flight 2 hrs and 50 minutes appx.
It depends on the type of traveling: Flying with an airplane is perhaps the fastest way to get to Varna and it wouldn't take more than 2-3 hrs (direct flight).
36 hours if you are fit, its about 1500 miles
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