Last August, I went to Saryuni Forest Road with my schoolmates while walking down the road. I saw a fruit that looked very tasty. I though it would be some kind of berry. So I took it and put it in my mouth. But it tasted bitter and stinging, so I spit it out. When I got back home, I searched internet using words like poisonous, plant, strawberry-like. and I found the fruit was called Chonnamsung, and it was a deadly enough to kill a person with a small amount. I also found that it was used as a death penalty in Chosun Dynasty. I could have died if I hadn't spit it out!
So please be aware of this plant before you go to Saryuni Forest Road. And not only eating fruits but also just touching this plant can cause allergic reactions to some people!