Originally Posted by
ludocdoc
You'll drive right by/through Yellowstone and Grand Teton National parks. My favorite places on earth. You could spend a week between the 2 and just skim the surface.
Also, if you go through either or both parks, you need a national parks pass of some sort. An adult pass is $80 for nationwide access for a year, I forget what the single entry fee was for both parks -- something like $25 US for a week. Seniors get a lifetime pass for $10, but not sure if that extends to non citizens.
Ditto on point 1. Traffic may and slow and accomodations hard to find at that time of year.
You'll likely also be driving by Glacier National Park (in Montana, just south of the Canadian border, where you can get the same pass before hand and visit another beautiful park.