Situated 25km southeast of Seoul, Namhansanseong Fortress sits 480m above sea level, aligning itself with the surrounding mountain ridges to maximize its defensive efficacy. The fortress is 12km in diameter and encompasses an area utilized as an emergency capital city during the Joseon Dynasty (1392-1910). The fortresses' strong East Asian architecture embodies the broad exchange between the four countries at the time (Joseon Dynasty of Korea, Azuchi-Momoyama Period of Japan, and the Ming and Qing Dynasties of China), particularly between the 16th and 18th centuries as the countries were often at war with each other. The technical development of weaponry and armaments during this period, like the use of gun powder in military warfare imported from Europe, also greatly influenced the architecture and layout of the fortress. Overall, Namhansanseong Fortress is an embodiment of how various defense mechanisms in Korea were put to use by combining a normal living environment with defense objectives, how Buddhism played an influential role in protecting the state, and how the fortress became a symbol of sovereignty in Korea.
Namhansanseong Fortress is an excellent example of the interchange of technological advances in fortress construction and weaponry in East Asia during a period of international wars. Namhansanseong Fortress is a unique fortress city with the purpose of functioning as an emergency capital for the protection of sovereignty and independence of the Joseon Dynasty. The walls and facilities utilizing the rugged terrain are an accumulation of the technological developments of Korean fortress architecture from the 7th century to the 19th century. The fortress is evidence of the struggle to survive and endure a painful history caused by the geopolitical power structure of East Asia at the time. Centered on these values, the province of Gyeonggi-do and the Gyeonggi Cultural Foundation, in their efforts to have Namhansanseong Fortress inscribed as a UNESCO World Heritage, pursued various projects and conducted countless research and investigations. As a result, in February 2011, the Cultural Heritage Administration of Korea designated Namhansanseong Fortress as a priority candidate among the tentative list of national heritages in Korea for pursuing inscription as a UNESCO World Heritage. Consequently, the nomination dossier of Namhansanseong Fortress was submitted in January 2013 and during the 38th World Heritage Committee (Doha, Qatar, June 2014), Namhansanseong Fortress was inscribed as a UNESCO World Heritage.