Zugaishima

Zugaishima (頭蓋島, Skull Island) is a large island off the coast of the Land of Earth. It is home to the ape, as well as a training place for Iwagakure shinobi. Ōnoki says that this is Iwagakure's version of 's. He also claims that none of the other nations know of the island's existance much less its location.