Jeongyang Sanseong Fortress (Wanggeomseong) in Yeongwol

This is a mountain fortress from the Three Kingdoms period located on Jeongyangsan Mountain in Yeongwol-eup. It was built of stone, making good use of the natural terrain of Jeongyangsan Mountain jutting out into the Namhangang River, and is presumed to have been first constructed between the late 5th and early 6th centuries, when the Three Kingdoms competed over the Han River basin. It continued to be used until the early Joseon period.
Along with the Jungwon Goguryeo Stele in Chungju and the Ondal Sanseong Fortress in Danyang, it is one of the Goguryeo cultural relics located in the central region. Located at an elevation of 550m at the end of the Bonghwang Mountain ridge, on a steep mountain peak, it has very good conditions as a mountain fortress. The overall planar shape of the fortress forms a wide trapezoid facing northwest.
This fortress is largely divided into an inner and an outer fortress. The inner fortress has a circumference of 1,060 m and the outer fortress 570 m, with the total length of the walls reaching 1,630 m. In terms of wall scale alone, it is comparable to Samnyeonsanseong Fortress in Boeun, which is considered the largest among Korea's ancient mountain fortresses. The outer fortress was built after the Goryeo period to increase the capacity of the inner fortress, using natural cliffs as walls in many parts and constructing artificial walls where necessary, showing the medieval characteristics of construction under emergency conditions.
Jeongyang Sanseong Fortress is not only the most important mountain fortress in the upper Han River region, but also the only fortress equipped with walls, gate sites, curved walls and chi walls, as well as later outer walls and blocking walls, and its state of preservation is good, giving it high historical and academic value. From this fortress, the movements of enemies entering Yeongwol along the Namhan River can be easily observed. In addition, as it is located at a geographically strategic point, it also became a contested site for the territorial expansion of the Three Kingdoms.