The Cherokee, when first they came to the Appalachians, claimed they encountered the Moon-eyed People, a diminutive race that lived underground. They were white with beards and had huge eyes, perhaps because of their subterranean lifestyle. They were also said to be blind during certain phases of the moon.
They built a long wall in Georgia, over 800 feet. This was because of a war with the Creeks, who at last defeated them. In North Carolina they were said to have lived in mound-like structures.
Who these people were and whether they ever existed, we cannot tell. But the wall is still there, in Fort Mountain, Georgia.