Yanase Futagozuka Kofun
Japan
The Yanase Futagozuka Kofun is a Kofun period burial mound located in the Yanase neighborhood the city of Annaka, Gunma Prefecture in the northern Kantō region of Japan. It was designated a National Historic Site of Japan in 2018, with the area under protection expanded in 2026. It is the only zenpō-kōen-fun), which is shaped like a keyhole, having one square end and one circular end, when viewed from above, found along the Usui River and one of the largest in Gunma Prefecture.
Monument data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).