Sure it flies.. Indeed Erzurum is one of the big cities of the east, and THY also files to much smaller cities... Turkish Airlines is the government airline, now there are commercial airlines, too. They also fly to Erzurum. In fact, there are also other factors that effect the decision of flying or not flying to a destination other than its population. Bursa is the 5th big city in Turkey, but because of its vicinity to ?stanbul, no flights are made to/from here.
There are 52 airports in Turkey, maybe more, because some are also being built...
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