Okanomiya is a shrine known as the guardian deity of Wakayama Castle. It is the guardian deity of the local village of Oka, and has a history of over 1000 years. Ever since Tokugawa Yorinobu entered Wakayama Castle, Okanomiya became the guardian deity of the castle. Also, when the fifth lord of the domain, Yoshimune, was born, it is said that the priest of the shrine adopted him as a parent. Oka no Miya is also known as the ``god of good luck'' because of Yoshimune's success in life, and many people from all over the country come to worship. The Okanosato Tumulus is also located within the precincts, and you can tour it for free.