Where does Between a rock and a hard place come from?

The origin of the saying is taken from the ancient Greek mythology of "The Odyssey". In his efforts to return home, Odysseys must pass between Scylla and Charybdis. Scylla was a horrible man-eating monster that struck from above on the cliffs (the "rock") while Charydbis was a treacherous whirlpool (the "hard place"). Hence "to be between a rock and a hard place" is to have a dilemma.