After 1,000 years of being colonized by the Northern feudal dynasties, in 938 Ngô Quyền defeated the Nam Hán (Chinese: Nan Han) troop, opening the country’s long period of independence. But then a state of power dispute took place and at last, the country was divided into 12 regions ruled by 12 warlords. Đinh Bộ Lĩnh defeated 12 warlords and unified the country. He ascended the throne, named the king as Đinh Tiên Hoàng, named the country Đại Cồ Việt and set up his capital in Hoa Lư (Now Ninh Bình province) as well as building Hoa Lư citadel. Hoa Lư ancient citadel was located in the land of Trường Yên commune, Hoa Lư district, Ninh Bình province now. Hoa Lư ancient citadel used to be the place living and working of the kings of 2 dynasties: Đinh, Tiền Lê, and early Lý dynasty.
Hoa Lư ancient citadel had an area of more than 1,000 hectares. It had two citadel wall rings adjacent to each other and a citadel ring at the back, forming the shape of the number 80. The researchers divided Hoa Lư ancient citadel into 3 citadels as follows:
Đông citadel (eastern citadel)
Đông citadel was about 140 hectares, located in the east. It was also called Ngoài citadel (outer citadel). There were 5 sections of the wall connecting the mountains, so the citadel wall ring was closed.
Đông citadel used to be the daily working place of Hoa Lư court. This is also place where Đinh Tiên Hoàng king temple and Lê Đại Hành king temple are located in the center. Đông citadel has still left many place names such as Cầu Đông market, Nhất Trụ pagoda, Cổ Am pagoda, Yên Trạch temple, Mã Yên mountain, Cột Cờ mountain, Sào Khê river.
Tây citadel (western citadel)
Tây citadel had the same area and was located to the west of Đông citadel, and also called Trong citadel (inter citadel). there were also 5 sections of artificial citadel wall connecting the mountains.
Tây citadel was home to the king’s family and a number of royal people and high-ranking government officials. There were also barracks of 3,000 soldiers protecting the king and the court. Currently, in the land of ancient Tây citadel, there are relics such as the Kim Ngân pagoda where the gold and silver were stored before, Duyên Ninh pagoda, Bim temple, Vực Vong temple.
Currently, the mountains still exist, but the sections of artificial citadel wall of Đông citadel and Tây citadel and the palaces are only vestiges excavated. Archaeologists dig a number of sections of the citadel-wall rings and find that there are foundations made of tree branches and many stakes made of wood driven deeply. The inside of the sections is made of bricks, up to 0.45 m thick, from 8-10 meters high. Many bricks have the size of 30 x 16 x 4 cm, are usually printed with the words “Đại Việt quốc thành chuyên” (the kind of bricks specially used to build the citadel of Đại Việt country) and “Giang Tây Quân”. The outside of the sections of the artificial citadel wall is the vestige of very thick earthen citadel wall.
Nam citadel also called Tràng An citadel was located in the south of Đông citadel and Tây citadel. It had an area larger than the other two citadels. Tràng An citadel had high mountains, deep moats, protecting the back of Đông citadel and Tây citadel. From here soldiers could quickly go in and out by waterway. Tràng An currently has many monuments describing the layout of the defense of 2 other citadels. Here, archaeologists also unearth the remains of prehistoric people and many antiques from the Đinh, Tiền Lê, and Trần dynasties. In the Trần dynasty, this place continued to be a base against Nguyên (Yuan) army. Currently, this is an ecological historical tourism route that attracting many geologists and history researchers.