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Gordian’s Knot

You wouldn’t expect something that looks as if it fell out of an infant’s pram to be quite so taxing. Billed as the world’s most difficult take-apart puzzle, this little number is named after the Gordian Knot of classical antiquity.

King Midas tied his ox-cart to a post with an intricate knot, declaring that the first to untie it would rule Asia. After four hundred years without a winner, Alexander the Great showed up, slashed it in half with his sword and claimed his prize. Cheating slightly, but whatever.

Unfortunately, hacking today’s version apart isn't strictly allowed. Rather, it consists of six interlocking pieces that require 69 moves to take apart. Good luck.