The Truong Yen Festival (Dinh-Le Kings Temples Festival) takes place on the 10th of the third lunar month, in Hoa Lu, the ancient capital of the Dai Co Viet Kingdom of Vietnam (10th century A.D.), in honour of Dinh and Le Kings.
The festival starts with a water procession, which leaves from the Dinh King's Temple, with colourful flags, the royal chair and a jar of holy water, to go to the Hoang Long River (Golden Dragon River) to take some water and finally return to the temple.
After the worshipping ceremonies held in both Dinh King and Le King Temples, visitors can burn joss sticks and visit ancient architectural structures of the ancient capital.
Several traditional games are played during the festival. For example, "Lau flag" (Reed flower) is a game that consists of performing the same manoeuvres young hero Dinh Bo Linh accomplished during his childhood.
The participants comprise a group of 100 boys and are divided into two opposing camps engaged in a mock battle. Recently, the conclusion of the festival has been marked by a new item: fireworks at the Buffalo Cave, near the Ma Yen Mountain.
The first stage of the fireworks provides the picture of a group of dancing people clad in clothes decorated with birds' feathers symbolizing a nation in peace. The second stage of the fireworks gives the picture of a mock battle with reed flags. The third stage provides the picture of Dinh Bo Linh clad in a royal dress, riding a dragon and overlying the Hoang Long River in order to establish the first Royal Court of Vietnam. The fourth stage involving big sky-rocket firecrackers which provide the picture of 9 dragons greeting a flag bearing the words "Thai Binh", the dynastic title of Dinh Tien Hoang King.