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.
There is also a rammed-earth mound measuring approximately 300 meters in length, about 3 meters in height, and roughly 21 meters in width at its base, situated in the rural area where the low hills at the southern foot of Ki Castle protrude from both the north and south. It is also thought to have been the site of a secondary defensive installation intended to safeguard the approach road to the castle.