We drove our coach about 250 miles, about four hours of driving, from Ephrata to Shelton, Washington.
Here’s a map showing our route, heading west (with the ultimate destination omitted for privacy):

An interactive map, with potential stops pinned:
There was roadworks on the bridge over the Columbia River, with a 9-foot width restriction, so we considered avoiding that and taking a more scenic route, as follows, but it would have added 1.5 hours to the travel, and been more stressful with curvy highway roads, so we stuck with the above route instead of this alternative:
I-90 West and the aforementioned Vantage Bridge:

Narrow, but good enough for trucks, so good enough for us:


Thorp Fruit & Antique Mall:

Rest area:

Wildlife bridge:

Keechelus Lake:

Snoqualmie Pass:

Crossover intersection:

Joining I-5 South:

Fuel stop:

Tacoma Dome:

Route 101 North:

We previously took this exit, but it is more difficult getting through Shelton:

Instead we took this exit, which is much more straightforward:

Downtown Shelton:
