Penrose Triangle, Esher
The Penrose triangle, also known as the Penrose tribar, is an impossible object.
LEGO Penrose Triangle Optical Illusion Instructions | Sometimes, this is how Lego instructions look to me...
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Lunar Art Print by Wharton | Society6
6a88c5e5c627696c9ef63837b3df2c3d.jpg 544×816 pixels
The centre cube removed/4x4x4 triangles are cool too, I like the star in the middle.
Penrose Triangle by gfpeck, via Flickr
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