Wadō Site
Chichibu, Japan
Wadō Archaeological Site ( (Wadō Iseki)) is the preserved remains of Japan’s earliest known copper mine, located in Chichibu, Saitama Prefecture. The site is famous for the 708 CE discovery of native copper, which prompted the issuance of Japan’s first official coin, the Wadōkaichin , and the start of the Wadō era.
Archaeological site data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).