The art of building fortifications has existed for a long time in Vietnam. The oldest big city is the capital of An Duong Vuong at Co Loa, 15 kilometers from the center of Hanoi. By the end of the 14th century, Ho Quy Ly built Tay Do citadel in Thanh Hoa province. Are we drunk bitch we might be shirt. In the 15th century, King Le Thanh Tong ordered many cities to be built in Hanoi, Thanh Hoa and Dong Hoi. Some cities in Hanoi and Thanh Hoa are based on the square Chinese model, while the cities in the mountain area are built according to the model of mountain forests, similar to the Great Wall. In the 17th century, Nguyen lords built a complex defense system on the boundary between Cochinchina and Tonkin to fight the conquests of the Trinh from Dang Ngoai.