Behind the Ky Dai is palace - one of the overall structures belongs to Hue ancient architecture complex. Ky Dai was built in the reign of 6th Gia Long (1807). Initiatively, it was very simple, however, during the Minh Mang dynasty, Ky Dai restored in the 1829, 1831 and 1849. Ky Dai has two parts: tower flag and pole flag.
Flag pole was built in the middle of the highest floor. Firstly, the flag pole was made from wood. In 1846, King Thieu Tri reconstructed new flag pole. In 1904, one typhoon damaged the flag pole and until the reign of King Thanh Thai, the flag pole was rebuilt a new one by cast iron.
At the beginning of 1947, in the Second war in Vietnam, one again, the flag pole in Hue was destroyed. Until 1948, it was rebuilt by steel rob with a height of 37 meters as we can see currently. Generally, the height from ground to the top of Ky Dai is 54.5 meters.
From the middle of 1994 to 1995, Hue monuments conservation center reconstructed Ky Dai with scale way and it took more 1.5 billion Vietnam dong.