Central area of ​​Thang Long Imperial Citadel - Hanoi. The 34th session of the World Heritage Committee meeting in Brazil on July 31, 2010 recognized the Thang Long Imperial Citadel Central Area. The central area of ​​Thang Long - Hanoi Imperial Citadel, with the core area of ​​the heritage area of ​​18,395 hectares (including the Hanoi Ancient Citadel Relic Area and 18 Hoang Dieu Archaeological Relic Area) and the buffer zone area of ​​108 hectares . The two areas of the heritage core area are a unified system located within the Thang Long Forbidden Citadel and are also the center of the Thang Long Imperial Citadel. The central area of ​​the Imperial Citadel of Thang Long - Hanoi is the most important part of the Thang Long Citadel - the capital of Dai Viet nation from the 11th to the 18th century. - Flag tower: built in 1805 at the same time the Nguyen Dynasty built the Vauban-style citadel, built on the old foundation of Tam Mon, the outer gate of the Forbidden City of the Le Dynasty. Ky Dai is one of the remaining intact structures from the Nguyen Dynasty. - Kinh Thien Palace foundation: built in the early Le dynasty (1428) on the foundation of Can Nguyen palace (later renamed Thien An palace) under the Ly and Tran dynasties. This location was originally the location of Nung Mountain (Long Do - Rong's Navel), considered the center of the Forbidden City and the Imperial Citadel, the place where the sacred energy of the country's mountains and rivers was cast according to traditional feng shui concepts, which passed down to the Imperial Citadel. The area still remains the palace's foundation with steps and stone railings carved with dragons in the 15th century. - Doan Mon: southern gate, is the main entrance to the Forbidden City, where Kinh Thien Palace and other palaces of the king are located. Since the Ly dynasty, a gate was built here, but the current Doan Mon gate was built by the early Le dynasty (15th century) and repaired and renovated under the Nguyen dynasty (19th century). Between Doan Mon and Kinh Thien Palace is Long Tri area - a space with very important political and spiritual cultural significance of the Forbidden City, where sacred political and religious rituals are held, such as events The King's Festival was held, the Quang Chieu lantern festival was held (in 1136), the Cam army parade was held (in 1351), and the nation's oath meeting was held (in 1128)... - Bac Mon: is the northern city gate, one of the only 5 remaining city gates of Hanoi Citadel under the Nguyen Dynasty, built in 1805. Bac Mon was built of brick with a stone archway. In 1999, archaeologists discovered the remains of a wall built of stone and masonry bricks, a 1.2m thick foundation and traces of another Le Dynasty architecture at a depth of 1.66m to 2m. ,20m. - Hau Lau: also known as Tinh Bac Lau, Princess Lau, Pagode des Dames, or Hau Dien building. This work was built in the Nguyen Dynasty (1821), as a resting place for the beautiful concubines in the king's entourage when traveling from Hue to the North. This work was destroyed around the end of the 19th century. The remaining architecture was rebuilt by the French. Archaeological relic site at 18 Hoang Dieu: located west of Kinh Thien Palace and was a part of the Forbidden City from the Ly Dynasty to the end of the Le Trung Hung Dynasty. The Forbidden City was the nerve center of the dynasties, where the country's most important ceremonies took place, and the working center and residence of the King and Royal Family during the Ly - Tran - Le dynasties. This relic area is 4,530 hectares wide, excavated since December 2002, divided into 4 areas, named A, B, C, D. Many traces of the foundations of architectural works were discovered here. Wooden structures have a large scale and many types of valuable relics, including architectural decorative materials, ceramics, metal objects, wooden objects, animal remains... dating from the 7th century - 9 to the 19th century, with hundreds of different models. At the archaeological site 18 Hoang Dieu, important palace vestiges were found. After 10 centuries of many wars, many historical changes and harsh natural conditions, the architectural vestiges and relics of the ancient palace are still relatively well preserved. ground. In the relic site, many foreign utensils and objects were also found, such as porcelain from West Asia, China, Japan, etc., reflecting the cultural exchange relationship between Thang Long and the world. This is the first time in Hanoi as well as the first time in the history of Vietnamese archeology that traces of the foundation of a high-class architectural complex have been found, especially the architectural vestiges of Thang Long Capital.