About 6 years ago Oskar van Deventer premiered his World Record 17 x 17 x 17 cube at the New York Puzzle Party. I was one of the 'expert witnesses' who wrote a letter to the officials at Guiness to confirm that this was indeed the largest n x n x n Rubik's Cube.
Nathan Wilson has shattered that record. See for yourself:

https://www.youtube.com/watch"v=lzzD1aNsLVU&app=desktop

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