Originally built by Baekje, it was occupied in turn by each of the Three Kingdoms.

The first mention of this fortress in historical records comes from the Samguk sagi's statement that King Chaekgye of Baekje ordered it to be fortified against an expected Goguryeo invasion.

At that time, Achasanseong would have played a key role in the defense of the Baekje capital Hansŏng from the north.

The fortress and the rest of the Han River valley were conquered by Silla in 553.

Achasanseong was designated as a historic landmark in 1973, and has since become a common local tourist destination.