Two monuments are in a house near the Sonjuk Bridge with a road in between. One of them was built in 1740 by King Yongjo and the other in 1872 by King Kojong to make the people loyal to the feudal Joson dynasty, following the example of Jong Mong Ju, a loyal subject of Koryo. The monuments stand on tortoise shells bearing the handwriting of the kings in praise of Jong Mong Ju.
The tortoises made up of monolith, patterns of lotus flowers and wriggling dragons carved on the eaves are precious historical and cultural heritage showing the remarkable cultural talent of the Korean people. It was registered as a world heritage site in Juche 102(2013).