There was a belief in Japan that mountains were a different world; for example, sorei (ancestral spirit, collective ancestral spirits which have lost their individualities, ancestor deified as a kami, spirit of a kami) return to the mountains and tanokami (deity of rice fields and harvests) comes down from a mountain.
日本には、祖霊は山に帰り、田の神は山から降りてくるなど、山は異界であるという観念があった。