The Blackfoot people referred to the Rocky Mountains as “the backbone of the world.” From the foothills of Rockies to the East extend the Great Plains. To the West, the Rockies ultimately drop off into the Pacific Ocean. Add in the amazing length of the Rockies from North to South and it is not hard to see that from the Blackfoots’ limited perspective at that time, they weren’t that far off the mark. There were trails that went across and over the Rockies at various places. In all probability they were originally game trails that were then use. . .