Some optical illusions are intentional like trompe l'oeil paintings in amusement parks or murals, or on a smaller scale like this young Japanese artist who can draw coke bottles which look like you could pick them up from the table, or this artist who draws anime characters that look like they're three dimensional.

However, sometimes we are faced with illusions and visually confusing sights which are produced entirely unintentionally. It only takes a combination of coincidental factors or viewing things from a certain angle to create something that causes us to question our eyes.

This is what happened to Twitter user Shimasao one evening as he was making his way to an izakaya (the Japanese equivalent of a gastropub) near Niigata Station in Niigata City. He was presumably heading to the second floor of the building where the izakaya was located, when he noticed something odd:

Apparently, the building has an unusual layout with two parallel and adjacent stairwells, one grey one connecting the first, second and third floors, and another white one connecting the first and third floors.

The second photo he took and the angle at which he (perhaps intentionally) shot it gives the scene a particularly Escherian quality, the opening in the wall separating the two staircases creating the gravity confusion famous from Escher's painting, "Relativity" [image on official M.C. Escher website].

It's not difficult to understand why the sudden sight of this unexpected configuration would confuse and disorient the viewer. To be honest, we're surprised there are not even any signs leading visitors to the pub (or at least, none where they ought to be).

Several comments, such as this one, alluded to a certain famous Dutch painter:

Others pointed out how dangerous it was for pub patrons, especially if they let themselves get drunk:

Let's hope that's just a joke, but if you're ever looking for an izakaya in the vicinity of Niigata Station, you may want to limit your search to buildings with elevators.