There is a turtle-shaped rock placed on a big, flat rock at Tonggae Harbor in Wangsan-ri.

The shape of the rock looks as if it opens its mouth toward Yeonpyeongdo of the Yellow Sea with its tail in the direction of Seopul village, and it looks like its poop is hanging toward the Hongmun Gate.
The legend of the turtle rock is as follows.

The ancestors of the people who lived in the village had settled at Seopul Sinbuldo of Yeongjongdo.

The ancestors plowed the fields and made rice paddies by banking up a stream. When the one of them, called Hyeongbo, died, a stranger stopped by the house and said, “I’m stopping by due to hunger.” The chief mourner treated the stranger well by serving food and spirits, even as he performed the funeral process.
The stranger, after he finished eating, then said,
“While I was exhausted from hunger, I was well treated, so as it is my duty to repay the kindness, I shall bestow a grave site.” The chief mourner agreed with the stranger, and they climbed a mountain to look for the site.
The stranger picked one site and said, “It must be in the direction of the turtle rock of Tonggae Harbor, Wangsan-ri.
If it is, the turtle rock will appear to eat large amounts of fish and excrete them in this direction.
Your future generations will then live in splendor.”

The chief mourner greatly appreciated this, and recommended that the stranger stay at his house for a while, but the stranger declined.
The chief mourner, who had been living a hard life of work, held the funeral following the stranger’s direction.
Then one day, one of his relatives, who was a mining engineer, visited Yeongjongdo to dig a mine.
As a result, they found a large amount of high-quality gold, and received a license and set up a gold mine. Some of their descendants joined in the mining industry, and the brothers Kim Jong-hyeon and Kim Dal-hyeon became rich.
The brothers performed beneficent work for the inhabitants, such as building stone bridges.
Many commemorative monuments were thus erected at Seopul, Sammok, and Yongyu School to honor the brothers’ charity.

According to the legend, the people who live at Tonggae Harbor in Wangsan-ri still believe that the turtle rock was there for the Samhyeon Branch of Gimhae Gim Clan.