Buyeo Naseong, also known as the Outer City Wall, was built to protect the capital of Baekje, Sabi. It has a x_height of about 84km. The wall surrouned Busosanseong Fortress and extended to the city of Buyeo. The wall is one of the oldest walls along with Naseong in Pyeongyang and it is estimated to have been built around 538, when the Baekje capital was changed from Woonjin (current, Gongju) to Sabi (current, Buyeo). The wall of the fortress starts from the site where Dongmun (East gate) was located to the area of Geumgang River, made by piling soil up. However, only a few traces remain of it's former glory. For now, it leaves a blurry trail including a 20m area to the east of Cheongsanseong Fortress, Dongmun Bridge from Seokmok-ri, and an area from Pilseobong Peak to Yeomchang-ri. While the outer wall is sharply sloped, the inner wall was built with a gentle slope to make it easier for horses to reach the guard posts on the top of the wall. Inside the fortress, the palace of Baekje, government offices, houses, temples, stores and protected facilities can be seen. The entire structure of Naseong Fortress features Geumgang River in the south and west sides, providing a natural double-defense system. The wall was one of the important outer defense facilities along with Cheongsanseong and Cheongmasanseong Fortresses. * Area: 554,591㎡