The tumulus was built by cutting a hill on the right bank of the Ashimori River in the western part of Okayama city.

The anterior portion is thought to have been modified in the Sengoku period, when a Shinto shrine was constructed, and a hamlet exists on the southeastern end of the mound.

The posterior portion was also flattened and was used as a fortification and lookout point during Toyotomi Hideyoshi's invasion of western Japan.

[2] Although it is the largest tumulus not under the control of the Imperial Household Agency, full-scale academic research has not been conducted to date, and the interior has not yet been excavated, so details of the burial chamber and grave goods are unknown.

From 2009 to 2012, a research team from Okayama University conducted an excavation outside of the designated historic site for the purpose of identifying the scale at the time of construction, the existence of a surrounding moat, and for confirmation of relics that can be used to estimate the construction period.