In a cave where many rock wall carvings, which ancient people of the Post-Jomon Period Late Stage (approximately 1600 to 1300 years ago) dug, remain, and earthenware, bone and antler tools, hearth traces, and others also remain, it is a globally also valuable nationally designated historic site.

Cave sites that leave carved drawings on rock walls, as for them, together with Otaru City's Temiya Cave, currently within Japan, there are no things that are compared.

There are over 800 carved drawings, and from things like people who disguised themselves, there are boats, fish, sea beasts, and things like four-legged animals.

Many human figures disguised with horns or wings exist, and this, as for it, is inferred to be a thing that represents a shaman, and it is thought that it might have been a place for some kind of religious ritual.

The cave, as for it, from the analysis of earthenware and bone and antler tools discovered from sedimentary soil layers, the fact that it is a site belonging to the Post-Jomon Period of approximately 2000 to 1500 years ago is known, and scholars and researchers from various countries are also visiting.