The Imperial Household Agency designates this location as Kōgyoku/Seimei's mausoleum. It is formally named Ochi-no-Okanoe no misasagi.Ponsonby-Fane, p. 420.
the imperial household agency designates this location as kōgyoku/seimei's mausoleum it is formally named ochi-no-okanoe no misasagiponsonby-fane p 420