Eternity is a puzzle devised by Christopher Monckton and consisting of 209 pieces, each of which is a 12-polydrafter (i.e., a compound of 30-60-90 triangles). The puzzle was introduced in Britain in June 1999. The goal of the puzzle is to arrange the pieces in the shape of a slightly nonregular dodecagon. A one-million-pound award was offered for the first solution to the puzzle, which was found by Alex Selby and Oliver Riordan on May 15, 2000. Their solution is illustrated above (puzzle pieces © 1999, Christopher Monckton). A second solution was subsequently found by Guenter Stertenbrink. Interestingly, neither of these solutions matches the six clues given by the puzzle's creator Christopher Monckton for his solution, which remains unknown.
Paradoxically, a harder puzzle is possible using a smaller number (about 140 pieces) of 12-polydrafters. This fact accounts for the reason that the discoverers of the two known solutions deliberately discarded Monckton's clues in order to open the way for possibly easier solutions.
