Is it realistic to visit these 3 in a 10 day time frame? If so what are the "can't miss sites? ". We love the outdoors/ hiking/ and special sites! Thanks.

mmcgriff,

I'd say it would be rushed and not ideal but possible.

My favorite hikes near Portland, Seattle & Vancouver were the following (I've been to Portland once, Seattle twice, Vancouver three times, for a few days each visit; I'm by no means an expert on the region, just telling you things I enjoyed):

Portland (area): Columbia River Gorge, Japanese Garden/International Rose Test Garden

Seattle: strolling along Alki Beach, the view from the Space Needle, biking the Burke-Gilman Trail from Lake Union to Lake Washington, strolling in Volunteer Park

Vancouver: Stanley Park, Lynn Canyon Suspension Bridge, Grouse Mountain, Van Dusen Gardens, Queen Elizabeth Park/Bloedel Conservatory, hiking on Bowen Island

Enjoy your trip to the Pacific Northwest whatever you decide. Daniel

In my view the most important sights are the Columbia River Gorge, the Oregon Coast (Cannon Beach and Ecola State Park minimum), Mt. Rainier, and the ferry from Seattle to Bainbridge Island or the Argosy Cruise in Seattle that goes through the locks.

Visiting Vancouver often requires long delays at the border which is time that could be spent visiting more of the Oregon Coast, the Olympic National Park, the San Juan Islands, or some of the other great natural attractions in Washington and Oregon.

HTtY

Rather than driving across the border I usually take the Amtrak bus between Vancouver and Seattle.
Last year I did drive my own car across at the Peace Arch (end of I-5). Getting into Canada was a minimal wait time. Coming back into the US took at least 3 times as long.
Each of the cities are fine as cities go. I just love the wide open spaces and hiking where you can't see any buildings within a mile.
The best part of Vancouver was the walk around the sea wall in Stanley Park.

Yes, visiting all three; Portland, Seattle, Vancouver can be done in 10-days. I'd split it up as follows:

Portland: 2-days - Columbia River Gorge, Mt Hood

Seattle: 3-days - Day trip to Mt Rainier, in town Pike Place Market & Seattle Center, Day hike (all-day) Mt Pilchuck or Mt Si (if really ambitious).

Vancouver: 3-days - Grouse Mountain tour, day trip to Victoria, biking or walking waterfront parks around harbor.

Flying or taking the train between the cities is a good idea (you can then rent a car locally when needed).