I recently purchased this slide on eBay recently. It depicts Farmrail (GNBC) 331 “Caddo”, a former Milwaukee GP9 tied down on a spur. I’m not exactly sure of the location or date, but I think its likely Elk City, OK in the mid 90’s.

I like this photo because there’s more to it than a simple roster shot. A modeler can learn a lot here. The buildings in the background, which don’t look rail-served, show that even rural Oklahoma has some very industrial looking structures. The track is fairly light rail, you can see some red mud washed up on the ballast. Its not completely overgrown, but there are some weeds. The switch stand also stands out.
I studied history in college, so conducting research through photographs like this is a part of the hobby I really enjoy.