As you walk along this path, you see piles of rock (sandstone) built up in layers. It is a hard rock that forms the cap of Lookout Mountain and the other ranges of the Cumberland Plateau. Beneath this sandstone are weaker formations of limestone and shale which, as they gradually erode back, undercut the caprock. The sandstone then breaks off forming cliffs all along the brow of the mountain.
This wall protected Confederate troops on top of the mountain from direct attack by Union forces during the Battle Above the Clouds.
More imaginative, though less scientific is this Cherokee Indian explanation for the existence of the mountains and valleys of East Tennessee:
"At first the earth was flat and very soft and wet. The animals were anxious to get down (from above in Galunlati, beyond the arch) and sent out different birds to see if it was yet dry, but they found no place to alight and came back again to Galunlati. At last, it seemed to be time, and they sent out the Great Buzzard, the father of all the buzzards we see now. He flew all over the earth, low down near the ground, and it was still soft. When he reached the Cherokee country, he was very tired, and his wings began to flap and strike the ground, and wherever they struck the earth there was a valley, and where they turned up again there was a mountain. When the animals above saw this, they were afraid that the whole world would be mountains, so they called him back, but the Cherokee country remains full of mountains to this day."