This is a Real Photo Post Card. The paper was made by Ansco of Binghamton NY. The trademark is CYKO. That trademark seems to have been discontinued in 1928, when Ansco merged with Agfa.
I acquired this card in East Tennessee from an individual who also didn’t know where it was, but was sold to me on the basis of the railroad stuff in the picture. I figured I could work out where it was. But I’ve had no luck. These places came and went fairly quickly in the early days of commercial coal mining.
This is a RPPC, a Real Photo Post Card, a one-off. The configuration around the “Place Stamp Here” on the back with all four corner triangles pointed up puts its manufacture between 1904 and 1918. I’m no expert on locomotives, but it looks like a Camelback 4-2-2 (note the bull’s horns above the lamp). Or, if I’m looking at it wrong, it could be a 4-6-0 (Clinchfield had four 4-6-0s early on, but no 4-2-2s) If this dates to the mid- to late-teens, this gang could be laying track for the Clinchfield Railroad, which may have occasioned the picture. Or they could be cleaning up a wreck.
The only reason I think it’s Clinchfield is because I bought it locally. Weak reasoning, I suppose.