 Cổ Loa Citadel

Cổ Loa Citadel () is an important fortified settlement and archaeological site in present-day Hanoi's Dong Anh district, about northeast of Hanoi city center.Various relics of the Bronze Age Phung Nguyen culture and Dong Son culture have been found in Cổ Loa, although it was later established as the capital of Âu Lạc Kingdom during the 3rd century BC (about 257 ).