Shrine where Ōyama Mitsu-no-Kami, the big brother of the sun goddess, Amaterasu Ōmikami, is worshipped. He has long been worshipped as the god of mountains, the ocean, and warriors. Inside the Museum of Treasures, you will find displays of armor, weapons, and more, including 8 National Treasures and 682 National Designated Important Cultural Properties.