Have you ever wondered what should be in the middle of M.C. Escher's famous 1956 lithography Prententenoonstelling? 
Well, here is the answer: itself of course!
You may recognise a number of the displayed prints inside the gallery, too. Too bad that there was a bit cut off at the right to make the original picture square (it is 320x315 (mm, I presume)), on the other hand the reconstruction has some extra bits there.