🇻🇳 Vietnam · Fortified city
Cổ Loa Citadel
Dong Son 3rd c BCE → Han 2nd c BCE → Ngo Quyen 938 CE · Dong Son Au Lac → Han → Dai Viet (Hanoi first capital)
Cổ Loa — spiral-walled citadel city (3rd c BCE–10th c CE) 17 km north Hanoi Old Quarter, excavated 1960s–2010s Nguyen Giang Hai (Vietnam Academy).