Ankan, 27th Emperor of #Japan, supposedly began his reign OTD in 531 https://cromwell-intl.com/travel/japan/kofun/empress-iwa-no-hime.html?s=mb #travel #history

Kofun of Empress Iwa no Hime — Megalithic Tombs of Japan's Ancient Rulers
Mausoleum of Empress Iwa no Hime. Kofun, megalithic tombs with distinctive keyhole shapes, were built in Japan from the early 3rd to the early 7th century CE. Today they are believed to be the tombs of Emperors.