My first experience of driving the area, was a pea-soup fog. During heavy snow there would be whiteouts as the winds would whip around you, making any features hard to see.... I wonder what this experience would have been like for the train drivers who would navigate this route.
As you come to the crossings or travel along the train trails - do you ever stop to look for a train and listen out for the ghostly choo choo whistle?
Maybe you should watch and wait for the train to come past and this might clarify where you can find the cache.
Watch out along the trail and listen out for the ghost train whistle. Choo-Choo!!