2-D Building Optical Illusion

Here is the Nix Professional Building that sits on the Riverwalk in San Antonio, Texas. It was completed in 1931 and was the first hospital in a skyscraper, and the only hospital with doctor's offices, hospital beds, and a parking garage all in one building.

San Antonio's 2D Building
Philip Armitage, (c) 1999
Used w/permission

Because of the building's sharp angles, the view from the Riverwalk presents an optical illusion that the facing wall is two-dimensional. The building's shape is in the form of an "L". The south side of the building is cut off diagonally by the riverwalk which runs through the building's block creating the illusion of a flat wall from the perspective of the river.

The internet is fascinating, I went all the way to a person in New Zealand to obtain a picture of a building in San Antonio, Texas, USA.