It wouldn't be any difficult to understand this interesting optical illusion if you have already one through my wall of water and gymnast's optical illusion!
You have to find out if those three men are on street (one is sitting on street bench and other two are standing on street putting their hands on street wall) or not?
Clue : The photo is taken cleverly, to understand this optical illusion you have to watch it in 'right to left' direction.
