The moulds are evidence of the moulding practice of bronze arrowheads in Co Loa thousands of years ago. 

Co Loa citadel was built during the end of the Hong Bang Dynasty (c. 257 BC), about 20km to the north of Hanoi’s centre. It was a place of worship for King An Duong Vuong and Princess My Chau, who are mentioned in legends passed down through generations. According to folklore, An Duong Vuong founded the ancient Vietnamese state of Au Lac and chose Co Loa as its capital.