뉴스레터

Question

When I hear the word Koguryo, the image that pops up in my mind is a long, strapping stretch of a mountain fortress following the ridge of the mountain. Why did the Koguryo people build so many mountain fortresses?

Answer

There are more than 200 Kogryo fortresses found so far. Even after more than 1,000 years, the historical legacy that the Koguryo people left still breathes with us here. The Koguryo fortresses can be categorized into three types: (1) flat-land fortress [平地城], (2) mountain fortress [山城]; (3) mixed-type fortress [平山城].

The Jangan [長安] Fortress surrounding the city of Pyeongyang in North Korea is a typical example of the mixed-type fortress that stretches over flat land, hills and mountains together. The Gungnae [國內] Fortress that surrounds Jian, China was built during the early to mid period of Koguryo and is an example of flat-land fortress. Koguryo flat-land fortresses can be found in other places as well. But a mountain fortress with walls built with layer of layer of well-honed corn-kernel-shaped stones that stretch over a mountain like a long drawn line is likely what comes to our mind in relation to Koguryo fortresses. Actually most of the Koguryo fortresses are in fact mountain fortresses.

So why did the Koguryo people build so many mountain fortresses? First of all, Koguryo was located in a mountainous region. Both Jolbon [卒本], where the Koguryo people is believed to have first found the state, and Gungnae, their second capital city, were in mountainous areas. Also, they likely preferred to build a castle in a mountainous region at the early stage of the kingdom when they were not very strong in order to protect themselves from external aggressions with help of rough topography. Using the steep mountain terrains, they built walls so that they could easily weaken the enemy’s offenses and survey the area. As their experiences were accumulated, their fortress-building skills were likely further developed, and they had to be. Koguryo fought the Xianbe’s Muryong clan in order to secure Liaodong and had to constantly fight off the relentless invasion of Sui and Tang which unified the Chinese Central Plain. The mountain fortresses provided an effective defense against enemies with much larger armies and superior wealth. Thus a well-made mountain fortress could be an impenetrable stronghold.

However, it is not the case that Koguryo mountain fortresses were used just for a wartime defense facility and refuge, since they were built almost everywhere not just around the border areas. Koguryo built mountain fortresses in provincial outposts which were installed in order to rule its vast territory. A mountain fortress also functioned as a town and municipal building where the provincial government was installed. In addition, a wide, flat square lot always can be found inside the walls of the mountain fortress, and it indicates that there was residential space for townspeople. This kind of mountain fortress is easily accessible from the lower land, so one can be inside the fortress while simply walking about.

These characteristics of Koguryo mountain fortresses suggest that early fortresses were usually built on the mountain top while later ones built along with hill lines embracing more space and a water source. However, we are only beginning to understand Koguryo mountain fortresses. The secrets of the past that the fortress remains are holding lie in thick walls, broken roof tiles and pieces of clay jars.