This ceremonial ground is where memorial services were once held to summon the spirits of the dead on the night before they were to be enshrined together in the Main Sanctuary as deities.
As the number of surviving family members attending the services increased, so did the size of the ground, and it was moved from a spot near where the Shrine Office now stands early in the Meiji era to the south side of the Main Hall, and finally to its current location in 1938.
The memorial services were held at a temporary shrine made of lumber with the bark left on, which was constructed on sacred ground measuring 5.5 by 7.3 meters, and designated in the center of a total area of about 2,300 square meters.
Today, only the site of that temporary shrine remains.