It is the associated shine of the inner shrine to worship Yamatohime-no-mikoto. Yamatohime-no-mikoto is the daughter of Emperor Suinin, Japan's 11th Emperor, and worshipped Amaterasu as the second generation of Saio. After progressing through the countries, she went into Ise. It was said that the shrine was built in the power of God. It is a relatively new shrine, as it was enshrined in 1923.
Yamatohime-no-Miya (associated shrine)