Yata no Kagami (八咫鏡?) is a sacred mirror that is part of the Imperial Regalia of Japan. It is said to be housed in Ise Shrine in Mie prefecture, Japan, although a lack of public access makes this difficult to verify. The Yata no Kagami represents "wisdom" or "honesty," depending on the source. Its name literally means "The Eight Hand Mirror," likely a reference to its width. Mirrors in ancient Japan represented truth because they merely reflected what was shown, and were a source of much mystique and reverence (being uncommon items). Japanese folklore is rich in stories of life before mirrors were commonplace.
In the Japanese mythology this mirror and the Yasakani no magatama were hung from a tree to lure out Amaterasu from a cave. They were given, with the sword Kusanagi, to Amaterasu's grandson, Ninigi-no-Mikoto, when he went to pacify Japan. From there the treasures passed into the hands of the Imperial House of Japan.
In the year 1040 (Chōkyū 1, 9th month), the Sacred Mirror was burned in a fire. Whether that mirror was irrevocably lost or not, the current government claims that there are three Yata no Kagami held at different Shinto shrines: one is in Meiji Jingu in Tokyo, one in Ise Jingu, and one in Atsuta Jingu in Nagoya.