Menger sponge
A Menger sponge is a square which is similar to itself. To make a Menger sponge, take a square, and cut a square hole in the middle. Repeat the process around the edge of the square 9 times. Do the same thing aforementioned infinitely.
A Menger sponge is a square which is similar to itself. To make a Menger sponge, take a square, and cut a square hole in the middle. Repeat the process around the edge of the square 9 times. Do the same thing aforementioned infinitely.