The Sakafune-ishi Stonework
Links:
https://asuka-japan-heritage.jp/global/en/saimei/detail/sakafuneishi_sa.html
https://asuka-japan-heritage.jp/global/en/images/download/saimei.pdf
https://thebrainchamber.com/the-sakafuneishi-stone/
https://factsanddetails.com/japan/cat25/sub168/item976.html
https://en.wikipedia.org/wiki/Empress_K%C5%8Dgyoku
https://www.megalithic.co.uk/article.php?sid=18823