The stone fortress of Namhansanseong, which was included in the UNESCO World Heritage List in 2014, is not only the symbol of Seongnam but also one of the main attractions of South Korea. Along with some other historical monuments of the 17th century, it is located on the Namhan Mountain on the territory of the national park of the same name.

This strong defensive fort was built in 632 for the sake of protecting the Korean Silla Kingdom from attacks of the great Chinese Empire of Tang. Later, the kings of the Goryeo dynasty again and again changed and expanded its boundaries. However, its appearance was well-preserved thanks to the representatives of the next dynasty of Joseon. Former Joseon kings made a lot to strengthen the ancient fortress, so when King Injo hid inside it, the Manchu people could not find him until the King himself decided to give in and, thus, opened the gates. There was installed the Samjeondo Monument in honor of this notable event.

The fort remained unchanged for several years. When King Sukjong got the power, he started to actively expand its borders and construct new buildings. For example, he built additional forts – Pongamson and Hanbonson. At the end of the 18th century, gray stone parapets were also added to the fortress.

Nowadays the famous historical citadel is an ancient defensive complex which is surrounded by stone castle walls with a length of more than 9 km and a height that reaches 7.5 meters. It has the restored northern and southern gates. On its territory, there is the western command post, the Buddhist temple of Cheongpyeongsa which was built in 1683, and the renowned tomb which was constructed in honor of a hung architect of the fortress southern part.   

Every year the fortress hosts rituals of remembrance and ancient ritual sacrifices that date back to the period of the Joseon dynasty.