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The following problem was composed by Johannes Hermann Zukertort:
In December 1885 Zukertort showed this problem to an amazed crowd in the Manhattan Chess Club.
Did you find the solution? No? And your favourite chess program is also clueless?
Here's a hint: At the time when this chess problem was composed the rule was that a pawn that reached the first rank of the opponent had to be promoted immediately to a piece of your choice — any piece from the 14 in the starting position not including pawns or kings! If you apply this rule creatively you will certainly find a solution to the problem! (See below, when ready.)
Johannes Hermann Zukertort