This Klein Bottle playground uses a mathematical model for its perforated climbing frame, in which there is no inside or outside, but only a continuous surface.

Created by artist and architect Vito Acconci, the play structure will be installed in the Miami Design District in 2014. Acconci was recently named Designer of the Year, and his title earned him the privilege of designing a large-scale work that will be climbed upon by children.

The trippy playground makes you want to be a child again and get lost in what appears to be a Klein Bottle. 

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