northwestern U.S. route

I have driven from Los Angeles to Ft. Stevens on Hwy 1 where available and 101 between. It's very pretty but it is very tiring. I don't mind the ups and downs, I don't like the brake/ accelerate/ brake/ accelerate etc. I had a IH Scout II and it was a stick shift without power steering. It wore me out driving in the mountains, now all the vehicles are, AT and PS. I guess my point is that the mountains are lovely and the roads that have no guard rails are fine, if UPS can travel them everyday, so can you. If you are just afraid, like my wife and DGD, go to sleep, take a muscle relaxant and sit back and relax. Heck, I wish my wife could drive those parts, I would love to be able to just look and enjoy the countryside.

As an aside, the first time my DW drove the MoHo was fine, we were in Alberta's wheat fields, the second time we were on the Alaska Hwy and she almost ran us into a gully. After that I watched everything she did and it seemed she was driving way too far to the right. That scares me and I jerked and twitched while she drove. Because I don't like to do that, it makes her nervous, I decided to find out how far right she really drive. I would look at the white shoulder line and then in the sideview mirror. Soon I could tell when the "wheels" were over the should line and when she was in her lane. Turns out she had the same problem when I drove. Now I know that she really was in her lane and not on the shoulder. Now when she hits the warning strip, it doesn't scare me, but it sure ruins my napping.

You might want to consider getting the Mountain Pass Directory

This would allow you to check different routes, easily.

In general though, any "US" route (vrs State Route) would be OK. There are exceptions, like Alt- US-14 in Wyoming, but those are covered in the directory.

Now if -you- would be OK is another question. Example traveling east bound on the Going to the Sun road (Glacier Park) can be just plain scary to people that aren't used to driving along a cliff. On average the Rangers have to drive someone off that road every week. They get on the road and freak out

Thanks so much for the replies, everyone! Paulj, thanks for the exact roads! That makes me much more confident! I didn't realize that you could see street views on google maps without an exact address. Neither of the picture you sent looked bad. The back road in California we were on had the white line on the edge of the road crumbling off into the drop-off below with curves and steep hills and no guard rails. Those pictures don't look bad. Thanks!

Yes, those are our exact stops. We tend to go places and stay a week, branching out from the location to see sights, and then making major drives on the weekend. The only one I'm wondering that might be pushing the limit is Alder Lake to Priest Lake. Maybe we'd need an overnight in a rest area. Have you done that? Thanks so much for the help!

Old guy - I might be a bit like your daughter. I'm glad you're not. And my husband's not. Maybe what I should do is purposely fall asleep and not think about it!

The upper part leaving Yellowstone is on the north side of the valley, so an east bound passenger would have a good view of the valley below.

Here's a sample Google Maps Streetview (but with guardrails)

https://maps.google.com/?ll=44.470725,-110.062237&spn=0.030073,0.078192&t=h&z=14&layer=c&cbll=44.470814,-110.061952&panoid=CY-ZV1jO_7MQM4LCzIuKFA&cbp=12,90.49,,0,-0.1

But if that's a problem, US12 just east of White Pass could be worse:
https://maps.google.com/?ll=46.656005,-121.337471&spn=0.014581,0.039096&t=p&z=15&layer=c&cbll=46.656003,-121.33759&panoid=ea3s9eUpEC24DjCd1Kx3vw&cbp=12,90.2,,0,-0.1
In this Streetview construction crews are repairing a washout.

And then there's Going to the Sun in Glacier - which could be scary even in the tour bus.

I beg to differ about the drive out of Yellowstone to Cody and not being scary. Last time I went that route there were no guard rails on the right hand side and my daughter was in my lap the entire drive. she has a problem with that type of heights.

Are these your only stops, or just significant ones? There's quite a distance between them

Fort Stevens State Park, Oregon

This is the north end of the Oregon coast. US101 all the way north from California is fine. Not a fast drive, but not difficult in any way. Busy in the summer.

Alder Lake, Washington

At the SW corner of Mt Rainier Nat Park. I assume you've chosen it as a base to see the park. From Ft Stevens the easy route would be US30 the Longview, I5 north, US12 east a bit, and WA7 to Alder Lake.

I assume then you want to head east. You have to cross the Cascades in one way or other. Through the park via Paradise to 123 is fine in the tow vehicle, but might not be what you want with full RV. Easiest might be 7 back to US12, and US12 east to Yakima. Or north to WA18 and then I90 over the mountains.

Priest Lake, Idaho

I assume you want I90 to Spokane (or US12 to US395 to I90), then US2 north to Priest River, and then north. Nothing difficult in this way.

Glacier NP (followed by possible stops in Missoula or Great Falls)

US2 to Glacier - easy. There are lots of threads about the Yellowstone to Glacier drive (look for either end point in the title).

West Yellowstone

You have a mountain drive out of Yellowstone to Cody, but nothing difficult or scary.

Cody

I assume you then want US16 over the Big Horn Mtns. Lots of threads on this.

Highway 1 above San Francisco is a beautiful drive but pretty winding. US 101 is pretty good all the way to Fort Stevens, unless there's construction or something.

Not familiar with your other locations but Highway 30 along the Columbia isn't bad. If you're not planning to stop in Portland, take the bridge to Longview on your way to I-5.