Maurits Cornelis Escher (1898–1972) was a Dutch graphic artist who made mathematically inspired woodcuts, lithographs, and mezzotints. He was the master of illusion.

Mark Veldhuysen made the following remarks about the town of Atrani's architecture which helps explain why Escher's perceptual distortions were in fact based on  reality.
Streets look like dead end streets but continue when climbing some stairs, at a completely different level. The roof of one house is the first floor of the next. What looks like someone's front door can actually be the entrance to a square with various side streets ...  M.C. Escher in Italy: The Trail Back" by Mark Veldhuysen published in M.C. Escher's Legacy: A Centennial Celebration

Relativity(1955) is very well known and here the normal laws of gravity don’t apply. It was his only major print to be created in both woodcut and lithograph format. In fact it makes me dizzy just looking at it!

Tomorrow we will be off to Spain to visit this glorious monument to Moorish architecture and craftsmanship. And then we will return to see what Escher made of it all and how it influenced his works.