My wife and I are planning this road trip mainly along the coast but with a detour to include Crater Lake in Oregon.
Do we need to pre-book hotels for this trip?
We have already booked hotels in Seattle and SF.
You should look into Crater Lake National Park area if you are planning to stay there...we were looking into staying there once and since there are limited places, like one or two, they fill up months in advance and we PNW'ers still get after it year round so please look into lodgings there and Seattle is a popular and beautiful place as well as the Oregon coast on your way up...so the long answer is...yes.
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Enjoy this fabulous trip! I have lived my entire life on the West Coast, Seattle, San Francisco and now San Diego. I miss very much, my favorite city, Seattle. It's a fabulous place to live. I am sure you have your plans while in the cities, but while in Seattle I recommend the Chihuly Garden and Glass, Olympic Sculpture Park, Pioneer Square and of course the Pike Place Market. Wander deep into the Market to get the real pulse. Skip Washington Coast, the Oregon coast is gorgeous! Cannon Beach being the best. Enjoy!!
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I would strongly recommend booking a hotel at Crater Lake... very popular place ...
Mary