Infinity Pools Optical Illusions Explained

Infinity pools are beautiful, when you are in and around them, they look like the water is endless, or as if it blends either with an infinite amount of water or the sky behind them.
We have sketched how they really work; while your eyes are seeing a border of water that blends with the large amounts of water in the background or with the sky.  The water at the far border of the pool, actually flows into a reservoir in the back which is pumped back into the pool.

Source : http://opticalillusiongames.com/infinity