Seobukgongsimdon (Northwestern Watchtower) was used by troops at the fortress to survey the nearby area for enemy movement and for any signs of attack. It is located near Hwaseomun Gate.
Construction was completed on March 10, 1796. Hwaseong was the first fortress to have this type of structure.
There is one other remaining watchtower at the fortress. The other is Dongbukgongsimdon (Northeastern Watchtower).
The structure was constructed with three levels. The lower level is made of stone. The upper level is made of brick layers. The middle layer is where troops would be located in times of attack or war.
In July 1797, King Jeongjo visited and proudly claimed that Seobukgongsimdon was an architectural marvel. It has since been designated a national treasure of South Korea.