Water road illusion?

Question

with the right conditions, when you are far away from this spot on the road but you can see it, it looks like their is water on the road but when you approach that spot on the road, the water just disappears. what creates this illusion?

Answer 1

It has to do with hot and cold air.  Since they have different densities when light passes through one to the other the light will bend and refract, and that's when you see the water like effect.