Power of the brain
Put your nose near the central bar and look at the scene. It should appear in three dimensions. If it is hard to see make sure your nose is against the bar and let your eyes relax and look straight ahead. There are two pictures, one at each end, taken from slightly different positions. The camera was moved to one side between shots roughly the distance between your eyes. When you put your nose by the bar your left eye sees one, your right eye the other and your brain puts them together into 3D.