Hwaseong Fortress, located in Gyeonggi-Do, was listed as a UNESCO World Heritage in 1997,  This was because the architecture was well representative of the palace and military constructions of the Jo-Seon Dynasty. 

The ink is a dark gray color, it was inspired by the beautiful appearance of the surrounding landscape, the piled-stone and brick fortress and roofs that can be seen from the main gate of Hwaseong. The ink has a warm gray tone.  This subtly yellowish dark gray is reminiscent of the warm brick color of the stone walls and tiled roofs seen in Hwaseong's fortress, delicately captures the beauty of Hwaseong.