Now I'm not too sure where the Snake River dumps into the Columbia, but it's somewhere near the Washington - Idaho border north of UP's crossing of the Blue Mountains. Both are major continental rivers in the same river system.

UP's mainline to the Northwest follows this river (system) on both sides of the Blue Mountains. I've often wondered why they chose the stiff mountain grades over over this very rugged mountain range; rather than just following the Snake until it reached the Columbia - it wasn't that far out of the way. I've always presumed the Snake River Gorge must of been somehow impassable. But certainly, it would have been a much lower grade line if closer to the rivers than over the Blue Mountains

Anyone know?

OPB