Suyangsan Fortress in Hakhyon-dong, Haeju City, South Hwanghae Province is a castle on Mt Suyang first built in the period of Koguryo.

   It is a typical Koguryo castle built along the peaks and ridges surrounding the valley to the south and the vast flatland against the mountain rising high to the north.

   Outside the water gate of the fortress is a cliff, and water flowing down from here forms a waterfall, which is called Suyangsan Falls.

   In the latter half of 14th century, when the foreign aggressors invaded here, the patriotic soldiers and people lured them into the east gate, pretending to retreat.

   The foreign aggressors who came into the fortress were annihilated in an ambush.

   In 1592, during the Imjin Patriotic War, the fortress made a great contribution to the national defense through the battles against the Japanese invaders.

   Suyangsan Fortress associated with the patriotism of our people is a precious historic relic which demonstrates the high level of fortification techniques in Koguryo period.