Have you ever walked somewhere that you could see from a distance, and thought it may take about 30 minutes to get to, but 2 hours later you still were not there? I have! This happens because your perspective can be altered depending on the nature of the atmosphere.
In this picture you can see how the trees in the foreground of the picture are well defined, but the farther away you look into the picture the blurrier it gets. You will also see that objects farther away look bluer than the objects closer up. Objects in the distance look bluer because we have to look through more air and particles like fog, rain, snow, pollution and other factors within our atmosphere.