The Royal Citadel lies on the archeological sites at18 Hoang Dieu Street and the Hanoi ancient citadel, covering an area of 18sq. metres.

They include diverse architectural forms, proving the long and traditional history of the Thang Long ancient capital over nearly 1,300 years, raging from the pre-Thang Long era (7^th-9^th  centuries) to the Dinh and pre-Le dynasties (10^th  centuries) and the Thang Long-Hanoi era.

The great cultural value of the Royal Citadel has been recorded in the profiles by the Hanoi municipal People’s Committee to UNESCO for recognition as a World Cultural Heritage site.