Potato Stone

• Potato Stone
  Locality: Karasawa, Aki-gun, Kohchi-ken, Japan
  
  Potato Stone is also called “Inedible Potato”. The name came from a legend. When the Buddhist monk Kukai begged for a potato in a village, he was rejected. So he turned potatoes into stones by a spell.
  The legend might have occurred because the stone looks very like sweet potato.
  This legend sounds rather childish for a grown up man, but the story is trying to tell us that “ Unkindness to a traveler brings misfortune”, in other words, “If you are kind to a traveler, happiness will come to you.”