This is the largest keyhole-shaped burial mound in the otokuni region, constructed during the middle of the kofun period. excavations have unearthed a large number of iron weapons, suggesting it was the tomb of a powerful figure who controlled the otokuni region west of the katsura river. furthermore, traces of a fortified enclosure and musket balls have been found, suggesting that akechi mitsuhide may have used it as his headquarters during the battle of yamazaki. it opened as a historical park in 2014. (note: there is no parking available.)