This fortress is located in symbolic Mountain Bongui that is 301.5m high above the sea level and that rises at the center of Chuncheon. The Bonguisanseong that was built along the line of peaks is a site of the history of resistance against foreign invasion to protect our country.

In 'Donggukyeojiseungram', the documents of the Joseon Dynasty, the size of the fortress is described as about 740m in length and 6m in height. As a result of an actual measurement, the fortress stands 1,241.5m in length and 5-6m in height. It was fortified with square stones that were trimmed randomly, and the height of the fortress was adjusted according to the topographical features of the area.

The sites where a fortress gate and a watchtower seem to have been located were all damaged, and on the other sites where the inside buildings of the fortress were likely to be built, the materials that were thought to be used for the foundation stone of the building are exposed and many broken tiles are scattered around. But we are not able to find out when this fortress was built, as there is no confirmed record about it.

Judging from its scale, it seems to have been a fortress constructed for defense (castle for refuge) against enemy attack. In the 40th year of the King Gojong's ruling of Goryo Kingdom (1253), when the 4th invasion was made by the Mongolians, the inhabitants of Chuncheon fought with their enemy, drinking the blood of cows and horses because of a shortage of water, and died bravely in battle. Therefore, this fortress called Chunjuseong at that time is a vivid spot of tragedy and resistance.

The Bonguisanseong was damaged with the elapse of time. Some parts (150m) of the fortress have been restored recently, but it has lost its original shape because the granites used for reconstruction were brought from other regions due to unavailability of the same material used for the construction of the original fortress.
Reference: A study on the surface of the ground of the Bonguisanseong in Chuncheon, published in Chuncheon City, Feb. 1993.
A monument was set up to memory of the deceased in Mt. Bonguisan and religious service is held annually during Soyang Festival.