The Celtic knot is a puzzle from an elite treasure trail that must be solved in order to proceed further. It was released on 4 August 2010 as part of the rework and expansion of the treasure trails reward system. To solve a real-life celtic knot puzzle, you must make the knot have rotational symmetry. A celtic knot puzzle has two solutions, as rotational symmetry can go two directions. An online interactive celtic knot puzzle can be found here.