This elegant design is really an impossible square that has been shaped into a circle. If you trace any surface around the figure you will travel from the inside to the outside.
Art: R. Ausbourne, based on an original design by Donald C. Simanek, 1996.
Notes
Displays a still image. Based on an original design by Donald C. Simanek, 1996: http://web.archive.org/web/20130311181942/http://www.lhup.edu/~DSIMANEK/3d/illus1.htm
Source
http://www.sandlotscience.com/Impossible/Impossible_Ring.htm (via web.archive.org)
Impossible Ring screenshots
