I was taking in the classic position light signals in Chicago and wandered down a little spur just to the west of them. The spur leads to an ADM mill and there are some VERY old rails being used. I have pictures showing dates from the teens! Can anyone shed light on how often cars are delivered and removed? Is there any schedule to it? Is there a possibility that the rails are original to the building of the spur? I'm going to poke around some fire insurance maps but I'd love any info anyone can provide.