It is said that Ooyamatsumizuka is the tumulus of Ooyamatsumi no Kami, a god and a father of Konohanasakuya-hime, situated at the top of the Ishinuki stairway with 169 steps extending from Ishinuki Jinja Shrine to the Saitobaru Plateau.
The tumulus is a 96-meter long Ekagami-type keyhole-shaped burial mound and the mound No.90 of the Saitobaru Burial Mounds.

【Address】
Oaza Miyake, Saito, Miyazaki (Saitobaru Burial Mounds)
【Telephone】
0983-43-3421 (Saito City Commerce, Industry and Tourism Division)
【Opening hours】
Open 24 hours
【Closed】
None
【Charge】
Free
【Parking】
Available (within the premises of the Saitobaru Burial Mounds)
【Website】
https://www.saito-kanko.jp/sightseeing/oyamazumizuka