Hue used to be the Capital of the Nguyen dynasty, the last royal monarchy in the history of Vietnam. Although the city had undergone great sufferings in the period of modern time, it still maintains a quite original face of an ancient oriental town, the most visible aspect of which is the complex of royal constructions and traditional monuments built in romantic natural landscapes. The architecture of the Ancient Capital of Hue reflects deeply Vietnamese traditional soul. In 1993, the complex of Hue monuments was included in UNESCO list of World Cultural Heritage. Since then, Hue - a cultural and tourist center of Vietnam - has become much more attractive to not only domestic and international visitors but also historians, architects and cultural researchers. The Hue Citadel, together with the vestiges of the Hue – Old National Capital - is an invaluable heritage of the people of the whole Vietnam nation and also of the humankind. We have a responsibility to preserve it with our understanding and with heartfelt appreciation for the cultural heritage of the nation. The book that you have in hand is a compilation of the Hue Citadel of the author - a person who has attached with his life and pen to Hue. If there is the Hue Studies, so Phan Thuan An were one of the experts on the Hue Studies who that whose writings are more worth reading.