From the style and motive used in this painting, I presume it was created by famous Sandro Del Prete. It depicts a passageway in Ticino, southernmost canton of Switzerland, which by the way is the only canton where Italian is the sole official language.
I like this one because it’s plain simple, and doesn’t favor none of the two illusory motives it holds. That being said, can you easily switch between old man’s profile and two of the Ticino people? Usually these kind of illusions struggle to push intended (illusory) motive to the front, while the other one is then too much blended with the background, thus making it much harder to see. I find it masterful when both motives have the same weight instead of when artists try to force the illusion!
BTW, how many of you noticed that we surpassed the 100 MILLION VISITOR milestone? I believe we are one of the rare webs that still use the counter (see footer). I’m aware there is zero chance that 100 million different people saw our website, yet makes you wonder how popular we became since our beginning.