The most spectacular route I know from East to West is to take Transcanadian Route1 through the Rockies to Vancouver on the Pacific Coast. You can take I80 or I90 as far West as Omaha or Sioux Falls (respectively) before swinging North on I29. Follow that to Winnepeg and then it's West on TC1 all the way to the Pacific Coast. It's even better to cross into Canada around Buffalo or Detroit (which is where I did it) but any way you get there, TC1 is awesome. Just don't plan on it being as fast at it would be in the US. It's takes longer, but it's a once-in-a-lifetime journey!
Buda_Jim

Buda_Jim