There is also a rammed-earth mound measuring about 300 meters in length, about 3 meters in height, and about 21 meters in width at the base located in the rural area where the low hills at the southern foot of Ki Castle protrude from the north and south. It is also believed to have been the site of a secondary fortification intended to protect the approach road to the castle.
Additionally, there exists a rammed-earth mound measuring roughly 300 meters in length, approximately 3 meters high, and about 21 meters wide at its base, located in a rural area where the low hills at the southern foot of Ki Castle jut out from both the north and south. It is believed to have served as a secondary defensive position designed to protect the road leading to the castle.