Maybe you have never seen petroglyphs before. They are rock carvings and these, at TrackRock, Georgia are estimated to be POSSIBLY as old as 8,000 to 1,000 B.C. Or possibly the early 19th century A.D.? You would think they could get a little closer in the date.
In 1867, conservationist John Muir traveled nearby and met a mountaineer who said, "It is called Track Gap ... from the great number of tracks in the rocks – bird tracks, bar tracks, hoss tracks, men tracks, all in the solid rock as if it had been mud."
I think it is just as easy to imagine they were early Cherokee reactions to extra-terrestrials.