Gongju Gongsanseong Fortress [UNESCO World Heritage] (공주 공산성 [유네스코 세계문화유산])

Gongju Gongsanseong Fortress is a Baekje-era hilltop fortress in Gongju, Chungcheongnam-do, inscribed as part of the UNESCO Baekje Historic Areas in 2015 along with the rest of the Baekje capital sites in Gongju, Buyeo, and Iksan. Originally called Ungjinseong, the fortress served as the royal stronghold during the Ungjin (Gongju) capital period of Baekje from 475 to 538 CE, after Baekje's earlier capital fell to Goguryeo. The current ramparts loop roughly 2.6 km around the hilltop above the Geumgang river bend, with restored stone walls, a series of named gates (Geumseo, Jinnam, Manharu pavilion), pavilions, and excavated foundation stones from royal-court buildings. A circuit walk along the wall takes about 90 minutes and gives clean views over Gongju and the Geumgang. Pairs naturally with the Songsan-ri Royal Tombs (also UNESCO) and the Gongju National Museum for a coherent Baekje-history day.