A research group of the Korean National Heritage Preservation Agency, together with researchers of the Global Environmental Information Institute of the State Academy of Sciences, analyzed the space distribution features about the places, in which mausoleums of kings of Koryo might exist, and succeeded in founding out the exact location of Suk Jong's mausoleum.

In union with researchers of the National Heritage Preservation Office in Kaesong City and Koryo Museum, they conducted excavation in Sonjok-ri for over 20 days from last May to June to find out his mausoleum.

Suk Jong was the third child of Mun Jong, king of Koryo in the 11th generation, and his original name was Wang Ong, who reigned for a decade from 1096 to 1105. The name of Suk Jong is his posthumous one.

The size of his mausoleum, located in the middle of somewhat low slope of a mountain, 3km west of the seat of Sonjok-ri, is north-south 29m long by west-east 13m wide.

The mausoleum has three sections, which are divided by four west-east embankments.

The Archaeology Society of the DPRK ascertained that the heritage was the mausoleum of Suk Jong.

It is of great significance in making clear the developed culture of Koryo, the first unified state of the Korean nation.