It is said that the origin of this festival dates back to 203 (regnal year 3), when Empress Jingu made a triumphal return from Silla after completing the conquest of the Three Kingdoms, she erected a large flag during the campaign and built a mound to store her armor and held a ritual here. The Fujimori Festival, held every year from May 1 to 5, is famous as the origin of the "Iris (Dragon Boat) Festival. The shrine is also known as a deity that protects horses, and many people involved in horse racing visit the shrine to pray. The hydrangea garden is open to the public from June to July, with approximately 3,500 hydrangea plants in full bloom.