Namhansanseong, an ancient strategic defense point located in Gwangju City, Gyeonggido Province, was designated as a UNESCO World Heritage site in 2014. Built on rough mountain terrain, the natural fortress was designed to serve as a temporary capital in case of emergencies. The valuable architectural heritage illustrates different development stages of fortress construction skills from the seventh to 19th centuries.
“In the 12th year of King Munmu, the 30th ruler of the Silla Dynasty, Jujangseong Fortress was built in the Hansan region, south of the Hangang River. The wall circumference measures 4,360 paces.”
It is recorded in the “History of the Three Kingdoms” that the ancient Korean kingdom of Silla constructed Namhansanseong in the Hangang River basin in the 7th century to fend off the invasion of the Tang Dynasty of China.
Some believe that the fortress was the castle town of King Onjo, the founder of the Baekje Kingdom. At the time of construction, the fortress walls stretched 8 kilometers across the rugged mountain ridge around 500 meters above sea level. It was a great location for a strategic stronghold. The walls were built along the valleys and mountain ridge so the enemy could hardly notice the fortress. Located at the entrance of Seoul, the fortress played a role in guarding the capital in the Hangang River basin.
Today, castle stones, stone platforms as well as a storage site from the Three Kingdoms Period still remain. The fortress was repeatedly rebuilt and expanded. During the Unified Silla era, it served as a defense facility to contain the Chinese in the northern part of the kingdom. Later, in the Goryeo era, the fortress repelled Mongol invaders. The fortress underwent a major renovation in the 17th century during the reign of King Injo, the 16th monarch of the Joseon Dynasty, to become the structure we see today.
“Listen, my loyal subjects.”
“We’re at your service, Your Majesty.”
“Outside the nation, the threats of the Later Jin Dynasty are intensifying. Inside the nation, we had to deal with the rebellion of Yi Gwal. In this precarious situation, I believe now is the time to enlarge Namhansanseong.”
“You have the right idea. It is indeed a heaven-sent fortress. Why don’t we turn it into a castle that is comfortable to live in but is difficult to invade from outside?”
“Are you suggesting that we utilize the steep mountain ridge and create a wide basin inside the fortress?”
“That’s right. If we add more defense facilities and build a temporary palace where Your Majesty can live during emergencies, I believe we can remain unshakable under any circumstances.”
“Excellent! We can create a “shelter,” where the royal family and subjects can evacuate. Then I can carry out both military and administrative affairs at the same time. Start the work immediately!”
In 1624, construction began to expand the mountain fortress. Two years later, the fortress was equipped with 1,897 Yeojang, 125 guard posts, 16 Ammun and three Ongseong. Yeojang is a low wall that enables soldiers to hide themselves and shoot arrows or guns at the enemy, while Ammun refers to a hidden gate. Ongseong is another wall built around a gate or wall to provide stronger protection. Inside the fortress, there were 80 wells and 45 ponds. A royal residence called Haenggung and a government office were also built, so that the king could administer state affairs at the fortress in the event of a national emergency.
After the renovation work, Namhansanseong was reborn as a temporary capital with strong fortifications spanning 11.7 kilometers. But Joseon’s largest fortress with military and administrative functions faced a serious crisis during the second Manchurian invasion.
“Your Majesty, the Qing Emperor Taizong is leading 100-thousand troops and moving toward the capital with crushing force. You have to evacuate immediately.”
“The Qing forces have already blocked the road linking Gimpo with Ganghwa. Where on earth should I evacuate to?”
“Your Majesty, we have Namhansanseong. It was reconstructed ten years ago. Food and soldiers are prepared there. You should move quickly to the fortress.”
In December 1636, the Qing Dynasty invaded Joseon. King Injo and the royal court evacuated to Namhansanseong. The Qing troops besieged the fortress and fired cannons. Inside the fortress, 14,000 Joseon soldiers resisted for 45 days, fighting back desperately.
Unfortunately, the much-awaited reinforcements never came. To make matters worse, Ganghwado Island fell into enemy hands. In January 1637, King Injo opened the fortress gate and surrendered.
Despite the painful and humiliating history, Namhansanseong still preserves the people’s spirit to protect their homeland. During the reign of King Sukjong in the late 17th century, the fortress walls were reinforced for stronger defense so they would not easily fall during an attack. In the years of King Yeongjo and King Jeongjo in the 18th century, gun emplacements were installed at the walls. During the era of King Sukjong, the Jwajeon shrine for royal ancestors and the Usil altar dedicated to the gods of earth and harvest were created at the palace inside the fortress. Also, a local governor’s office called Jwaseungdang was built during the reign of King Sunjo. The fortress was repeatedly expanded until the 19th century to respond effectively to potential crises.
Since the Three Kingdoms period, Namhansanseong had safeguarded the central part of the Korean Peninsula as a strategic defense facility and served as a temporary capital during war. The fortress provides a comprehensive illustration of various skills related to military defense as well as fortress construction techniques in line with the changes of the times. Patriotic spirit and courage are felt in this holy place that embodies the ardent wish to overcome national crises.