Sanmen Island, also known as Yeouido, is located at the confluence of Dapeng Bay and Daya Bay. There are several peaks that can climb the view and a vast natural freshwater lake, as well as beaches, colored rocky beaches and rich vegetation. Wait. Sanmen Island is a small island that can see the clear water. It is located in the middle of the sea, so there is less human pollution, so it is a bit more pure.