Hello Fodors! New to the site. We’re planning a 10-day trip in September to the Pacific Northwest, flying in and out of Portland. Not sure if what we’ve come up with here makes sense and would love your thoughts!

Day 1: Arrive Portland
Day 2: explore Portland
Day 3: Scenic drive to Seattle (possibly by way of Mt. St. Helen’s)
Day 4: explore Seattle
Day 5: Scenic drive to Vancouver (by way of Mukilteo, ferry to Whidbey Island, Deception Pass, Chuckanut Drive, into Bellingham and up I-5 to the border)
Day 6: explore Vancouver
Day 7: explore Vancouver
Day 8: explore Vancouver (Maybe we go to Vancouver Island on Day 8 instead of 9?)
Day 9: ferry to Vancouver Island (ferry to Nanaimo then explore VI and drive to Victoria). (Stay in Victoria?)
Day 10: ferry to Port Angeles, WA and drive to Portland

Thanks in advance for your suggestions!

Perhaps you've been in the NW many times previously. If not, you are overlooking some highlights or the area including: the Columbia River Gorge, the Oregon Coast, Mt. Rainier and Olympic National Park.

HTtY

With only ten days round trip into/out of Portland, skip British Columbia and stick to Oregon and Washington. Or do just Seattle and British Columbia. (Is it impossible to "open jaw" into one city and out of another? Not sure about car rental one-way drop-off fee but it may not be much, at least for Oregon-Washington.)

I'd definitely add at least a half day from Portland to the Columbia River Gorge (lots of waterfalls, beautiful scenery, great hiking opportunities) and at least a night or two out on the Oregon coast. You could do three nights in Portland, three in Seattle, two or three on the Oregon Coast, and one or two somewhere else (Olympic National Park?).

The drive from Portland to Seattle isn't amazingly scenic even if you detour to Mt. St. Helens - though the visitor's center at Johnston Ridge Observtory is great and worth the detour. Note that St. Helens won't have much snow on it in September so may not be as pretty as it is in the winter or spring.

You can see enough of the ocean in Oregon and Washington without riding any ferries IMO.
There are 4 Amtrak buses and 2 Amtrak Cascades trains daily from Vancouver BC to Seattle.
Spend a little more time in Oregon. We have a pretty spectacular mountain (Hood) very close to the Columbia River Gorge.

I would ride a Ferry any day over a train. Just my opinion.

Frankly, with only 10 days, I would stick to just Portland area or just Seattle area and explore what there is around either of those. The two cities are great, but HTTY suggests you missing the real gems.