Buso Sanseong (Hanja: 扶蘇山城; Historic Site No. 5) is a mud fortress located on top of Mount Buso (alt. 106m) in Ssangbuk-ri san 4-beonji, Buyeo-eup, Buyeo County, Southern Chungcheong Province. The fortress is estimated by some to have been built around 538 AD (16th year of King Seong) to protect Sabi (nowadays Buyeo County), which was once the capital of the Baekje Kingdom. Other historians, however, believe that the fortress was already in place by 500 AD (22nd year of King Dongseong) and modified in 605 (6th year of King Mu) into the structure we see today. This fortress witnessed the demise of Baekje Kingdom during the reign of King Uija.
In 660, the southeastern kingdom of Silla, with its capital at Gyeongju, determined to end the warfare of Three Kingdoms Period, once and for all. Silla and its ally, Tang China, launched a two-pronged invasion of Baekje. The allied force, led by legendary Silla commander Kim Yu-sin and great Chinese general Su Dingfang (who would later earn glory expanding Chinese influence in Central Asia), defeated Baekje’s army (led by the tragically heroic General Gyebaek) at the Battle of Hwangsanbeol and laid siege to the royal capital of Sabi, modern Buyeo.
King Uija and the crown prince managed to escape to Ungjin, (nowadays Gongju City), but the rest of the court took protection behind the walls of Buso Fortress. There was nothing the defenders could do, however, and the fortress fell. The Samguk Yusa, an ancient history book, accounts that, rather than surrender themselves to the Silla and Chinese troops, some 3,000 court ladies leapt to their deaths from Nakhwa-am, their fluttering robes resembling falling flower petals as they crashed into the waves of the Baengma River below.
Mount Buso was once considered the guardian mountain of Buyeo and is home to historic landmarks from the Baekje Kingdom (18 BC-660 AD). In addition to Buso Sanseong, some of the most famous sites on the mountain include Baekhwajeong Pavilion, Sajaru Pavilion, Banwollu Pavilion, Yeongillu Pavilion, Samchungsa Shrine (dedicated to three loyal subjects of the Baekje Kingdom), Gungnyeosa Shrine, Goransa Temple, Gunchangji (military warehouse site), and Suhyeoljugeoji (site of pit houses for the Baekje soldiers).
In either case, some parts of the fortress were reconstructed during the Unified Silla Kingdom (676-935 AD) and modified again in the Goryeo (918-1392) and Joseon (1392-1910) eras.
Today, there’s not much left of the fortress or the palace facilities that adorned it, other than some earthworks and the foundations of old temples and pavilions. In more recent decades, some Korean traditional pavilions and other structures have been built on or moved to the hillock, including the Yeongillu pavilion, relocated to the fortress in 1964.
All in all, Buso Sanseong (entry: 2,000 won) is a pleasant place to stretch your legs — the hillock is criss-crossed with paths that are pleasantly shaded by the trees of the forest that covers the park.