The remains of the 855-foot stone wall that gives Fort Mountain its name wind like a snake around the northeast Georgia park,and its very presence begs a question:Who put them there? A Cherokee legend attributes the wall to a mysterious band of "moon-eyed people" led by a Welsh prince named Madoc who appeared in the area more than 300 years before Columbus sailed to America. A plaque at the wall says matter-of-factly it was built by Madoc and his Welsh followers,but most professional archeologists give no credence to the legend. "There has been no archaeological evidence to back up stories...