CP and UP started in I believe 1861. Until they built the first transcontinental line (completed 1867) there really wasn't much going on trainwise in the west, at least between the Mississippi and California/west coast. For example, the reason for the great cattle drives of the 1870's was that from Texas the nearest railroad line was in Kansas, they had to walk the cattle that far to ship them to Chicago or wherever to the meat packing plants.