Although you may not see signs of civilization nearby, that doesn't meant that it is old enough to have any KGC connection, unless they have been active there in the last 20 years. It doesn't take that long to have a place grow up and cover everything.
It really looks like some sort of loading ramp. Very familiar to me, but can't remember where I saw those ramps before. However, without some form of preservation such as paint, I doubt they have been there more than 20 years based on the small amount of rust.
EDIT: These pieces resemble very closely the ramps on a trailer we used for moving our "ditch witch" when I worked for an underground services company putting in water systems for rural water systems. Two ramps welded together. I would look for a second one parallel to the first one . . . about 2-3 feet away. They made an excellent ramp for working on cars when attached to black iron pipe in that way. The round rods were for traction with our tractor's tires.