Knight's Tour

The Knight’s Tour is a puzze to find how a chess knight can traverse a grid visiting each square only once. When a line transverses a grid so that it never visits a vertex more than once and ends where it begins, this is called a Hamiltonian path.

One solution to the Knight’s Tour was given by the Mechanical Turk, a chess-playing automaton created in 1770. This machine toured championships and won competitions against real live players. However the automaton was really run by skilled chess players until it was exposed as a hoax.