Dan The Yadkin River retains its name Yadkin until it flows past High Rock Dam, Tuckertown Dam, the Narrows Dam and then at the confluence of the Uwharrie River. it becomes the Great Pee Dee River. I would note that the very first trinkle of water starts in the parking lot of the Green Park Inn in Blowing Rock. Further, I would consider any county that has a border on the Yadkin is in the Yadkin Valley..I think that only Davie Coshould qualify as in the forks of the Yadkin but that would be hard for folks to accept. The Yadkin River also has a Little Yadkin River which has not been mentioned. It flows into the main River NE of East Bendin Yadkin Co. AL of Yadkin Co. NC