The octopus stone, Taiko-ishi 蛸石 (also called “Drum Rock”) is a large stone near the castle’s Sakura Gate.  It is one of the largest megaliths at the castle (by face area), at 5.5×11.7 meters and over 130 tons, and its name is derived from the octopus shape some say is visible on its lower left corner.  Not everyone agrees about that now, though.  The postcard is old and unused.  Grade: 1