Impossible staircase

The impossible staircase, also known as the Penrose stairs, is an optical illusion of never-ending stairs.

Named after its inventor, the mathematician Roger Penrose, who first introduced this concept in the 1950s, the illusion uses multiple, conflicting lines of perspective to trick your eye into seeing the stairs continually rise.

I imagined this is what would happen if you visited M.C. Escher's house. Escher made the staircase famous in his drawings Ascending Descending, and Waterfall, after being introduced to it by Roger Penrose, who Escher had inspired to create some impossible shapes.

The mindbending Penrose steps also appear in the movie Inception.

It took quite a long time to get the perspective right. Ultimately, I used the handy tutorial on drawing the Penrose staircase from the excellent Circle Line Art School.

Also see: the ring-segment illusion, the frequency illusion, the moon illusion, and the Hermann Grid, necker cube, and blivet