Sanzu Plains

The Sanzu Plains ( 三途ヶ原 , Sanzu Gahara ) are located in the Land of Earth . According to the Third Tsuchikage , the Sanzu Plains are protected by a powerful barrier, preventing those who enter from leaving and using jutsu . It is also a training ground for Iwa shinobi by finding their "heart stone" ( 心の石 , kokoro no ishi ) in order to leave. It also contains a giant-maned wolf.