Originally Posted by High Country Herb
Another one is I-5 from Lake Shasta, CA to the Canadian border. It is heavily forested most of the way, with lots of snowy peaks and lakes to look at.
You can stop at Eugene, OR for that trip... The rest is rather straight, flat and too much traffic / cops.
I-84 east of Portland through the Columbia Gorge is about as scenic as it gets with sweepers.
I'll second the I-90 sections from Northern ID to Missoula