Baekje Implemented Royal Fortress-Level Technology in Chungju

Largest Wooden Water Reservoir and Rammed-Earth Wall Discovered at Jangmisan Fortress

The results of archaeological excavations have revealed traces indicating that Baekje implemented capital-level technologies—rarely used in local fortresses—at Chungju.

Chungju Jangmisanseong Wooden Reservoir Overview / Cultural Heritage Administration.

On September 1, the National Institute of Jungwon Cultural Heritage, part of the National Research Institute of Cultural Heritage, announced findings demonstrating that Baekje established and operated Chungju as a key strategic base in the Jungwon region.

This is the outcome of a long-term research initiative jointly conducted by the National Heritage Administration, North Chungcheong Province, and Chungju City since the second half of 2022. Beneath the existing stone fortress wall, a sequence of discoveries was made: remains of Baekje’s Hanseong-period earthen fortress, living quarters, and a large wooden reservoir.

The most remarkable discovery is the wooden reservoir unearthed in the northern valley inside the fortress. This reservoir is the largest from Baekje's Hanseong period found to date, with each side of the square measuring approximately 6.7 meters and a depth of about 1.8 meters. Wooden beams over 7 meters long were processed whole and stacked in nine interlocking tiers for each wall. An institute official explained, “The reservoir was designed to collect and control water flowing into the valley, showcasing Baekje’s sophisticated water resource management system and civil engineering technology from 1,600 years ago.”

Detailed View of the Earthwork Wall at Jangmisan Fortress in Chungju / Cultural Heritage Administration.

The research team meticulously examined even the smallest traces in the soil. They used water screening to recover fine artifacts and organic materials from the excavated soil. As a result, they identified over 50 species of cultivated and wild plants, including rice, red beans, and soybeans, as well as animal bones from cattle, pigs, and dogs. They also unearthed a bamboo basket and an ox nose ring, which are considered the earliest physical examples found in Korea, along with an axe with its handle fully intact—providing clues for reconstructing the daily lives and surrounding environment of the people at Jangmisanseong fortress in the fifth century.

The findings did not stop at the reservoir. Underneath the stone fortress wall, they uncovered a rammed earth wall—a construction technique typically reserved for royal fortresses. Numerous central-style Baekje pottery and lacquerware items from the Hanseong period were also unearthed nearby. Rammed earth construction, which involves layering and compacting soil, was mainly used in Baekje’s royal fortresses, such as Pungnap Earthen Fortress and Mongchon Earthen Fortress.

Chungju Jangmisanseong Earthen Fortress Wall Investigation Scene / National Heritage Administration.

An institute official commented, “Jangmisanseong appears to have been more than just a defensive facility; it was a core strategic hub in the Jungwon region, systematically built and operated by Baekje through the active deployment of central technologies and human and material resources.”

The institute is holding a special exhibition of excavated artifacts at the Kugwongwan exhibition hall until December 31. On September 4 and 5, the excavation site will be open to the general public.

This content was produced with the assistance of AI translation services.