According to the book "Ngọc phả cổ lục" kept at Thượng temple in Cổ Loa vestige site, Cổ Loa commune, Đông Anh district, Hanoi city, 7th of the third month of the lunar calendar is the day “the King pass away" also known as the day of the death of King An Dương Vương - the successor of the Hùng Kings’ period - founded Âu Lạc state and relocated the capital from Phong Châu (Bạch Hạc, Việt Trì, Phú Thọ) to Cổ Loa, built a citadel, fought against invaders, and developed agricultural production and expanding the country in the nation's history of building and defending the country in the 3rd century BC. King An Dương Vương was granted conferment as God by the Lê - Nguyễn dynasties with respect and admiration as a "talented man in the world" who deserved the credit for building the country and has been worshipped by the Cổ Loa residents forever.

In order to pay tribute to ancestors, to educate the traditional morality of when drinking water, think of its source, on the anniversary of the death of King An Duong Vuong on 7th March – Lunar Calendar every year, Thang Long - Hanoi Heritage Conservation Center, Management Department of Cổ Loa Vestige Site held incense offering ceremony to commemorate King An Duong Vuong at Thuong temple. Attending were the Institute for Conservation of Monuments - Ministry of Culture, Sports and Tourism; Hanoi Trade and Investment Promotion and Tourism Center, Thang Long - Hanoi Heritage Conservation Center, Co Loa Relics Management Board; Đông Anh District Party Committee - People's Committee; Cổ Loa commune Party Committee - People's Council - People's Committee - Fatherland Front Committee, Club of Former “Quan đám” of Cổ Loa commune, along with a large number of press reporters - television stations, unions, people of Co Loa commune, Dong Anh district and visitors  respectfully offered incense to commemorate King An Dương Vương at Thượng Temple.

Representatives of agencies, departments, and unions offered incense to commemorate King An Duong Vuong at the upper dragon yard

The Co Loa Former “Quan đám” Club offers incense to King An Dương Vương at the sanctuary of Thuong Temple

The altar of King An Dương Vương at the sanctuary of Thuong temple

MANAGEMENT DEPARTMENT OF CO LOA VESTIGE SITE