Photo taken on June 13, 2013 shows the south gate of the Citadel of the Ho Dynasty in Thanh Hoa Province, Vietnam. The Citadel of the Ho Dynasty once was the capital of Vietnam's Ho Dynasty (1400-1407). The citadel, built according to the "feng shui" principles, sited in a landscape of great scenic beauty, represents a new style of south-east Asian imperial cities. After over 600 years, however, the citadel is left with nothing but the ruined city wall and gates. (Xinhua/Ho Nhu Y)