Here are some of the impossible structures, though they appear to be impossible for construction but they are made possible. These pictures have not been edited.

Penrose Impossible Triangle

Many think this can't be done. But it is actually possible! And if you wish to construct your own Penrose Impossible Triangle then just download and print the PDF. What more, you can change the dimensions as you like & even shade it or color it too.
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Wheel

If you cover about 1/3 of the picture at either end, then the picture looks like any other ordinary picture of washer or ring. In this only two colors have been used just like Mobius strip, has only two faces. "One reader says this isn't an illusion, for you can make one of flexible material, and he mailed me a model made from foam strip. However, while you can do this with a strip of square cross section, my illusion above has a rectangular cross section. He makes a valid point, however, he'll have to go to a lot more trouble to make each face change width as you go around 180°.
Then I devised this picture I thought that it might be an entirely original illusion. But then I noticed an advertisement with the corporate logo of the Canstar corporation, a manufacturer of fiber optics."
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Real life impossible object

So how was this constructed? Here you can see how this construction was built:

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Impossible wooden structure

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Amazing wooden structure