Thăng Long Citadel is a historic site located in Hanoi, Vietnam. It served as the political center of the country for over a thousand years, beginning in the 10th century. The citadel is recognized for its unique architecture, which blends elements from various dynasties, including the Ly, Tran, and Le dynasties. In 2010, Thăng Long Citadel was designated a UNESCO World Heritage Site due to its cultural significance and historical value. The site features ancient walls, gates, and remnants of royal palaces, showcasing the rich history of Vietnam and its imperial past.