Terrain glitches: Some airports are wayyyyy higher than they should be and the runways are basically on the top of what looks like a 1000ft platform when they are actually way lower in real life. I
Location glitches: The runways sometimes do not line up with where they would be in real life. In fact, sometimes I will see the satellite image of the real runway several meters away from where the runway in the game is. This also means that airports spawn inside of a mountain and are frustrating to deal with.
I have inserted a few images as examples: