Haraido Oji is the final oji before arriving at Kumano Hongu Grand Shrine. Harau means " to purify," and do means "door." Pilgrims wanted to approach the gods with a pure heart and clean body, so ritual purifications took place here.

The approach to Kumano Hongu Taisha (Grand Shrine) up until about a hundred years ago would continue past Haraido Oji over a steep downhill path of stones leading down to the delta where three rivers met. Along the path there were inns at which people could rest before making the final approach to the grand shrine. After the big flood of 1889, the grand shrine was relocated on the mountain near Haraido Oji. It is less than one hundred meters to the back of the relocated shrine.