Octopus stone

The octopus stone, Taiko-ishi 蛸石 (also called "Drum Rock") is a large stone at Osaka Castle in Japan. The stone is near Sakura Gate.

It is one of the largest of several megaliths at the castle (by face area), at 5.5×11.7 meters and over 120 tonne. Its name is derived from the octopus shape visible on its lower left corner.