You are in the CarrTracks website Picture Gallery.
It is much easier to photograph trains on the middle horseshoe curve from just off the road. Except for the broad sweeping curve, this looks like a model railroad with tracks stacked up a hillside. Engines 2605, 2735, 5191, and 2582 guide an eastbound train down the mountain on March 14, 1981.
Three months later the lower track is obscured by the trees and new growth. Engines 6141 and 6147 pull a special passenger train through the middle horseshoe curve on May 23. Disk 127