Khun Chhang Khun Phen stupa sits on a rock in the middle of the sea tributary, about 1 kilometer from the provincial town. The stupa is 4 meters high and made of concrete. Because the site is small-only 40 square meters, including the stupa-it can accommodate only 10 to 15 visitors at a time. The stupa is about 1 kilometer from the provincial town.

Koh Kong residents worship there and often visit the site on national holidays and traditional festivals. Khun Chhang Khun Phen is related to a Khmer legend. Once upon a time, there was villager's daughter named Thim, who was loved by a man named Khun Chhang. Khun Chhang was bold-headed and not very handsome, but his family was rich.Thim, however, did not love Khun Chhang, they became engaged and Khun Chhang married her.

She later betrayed her husband to love a commander named Khun Phen. When Khun Chhang learned of his wife's affair, he complained to the King. The King decided to cut Thim's body into two parts. After Thim died, Khun Chhang buried her at the same place where she was killed. Because he wanted her to be reincarnated, Khun Chhang put up a soul flag pole on the east bank of the stream, facing where Thim was buried. Then he built a stupa in memory of their love. Later, the west bank of the stream was named Chetdey (a stupa) village, and the east bank was named Dangtung (a flage pole) village.