I was watching these last night (at speed 2x) with some music in the background, and they really give you a nice tour of the area. Recommend it. Its been two years since I've visited here, and these make we want to go back.
Recommend 2x speed though. Shorter, and cover more distance quickly.
Most youtube drivelapses are shit, but these are actually really good and give you a nice tour. Almost like you where there.
Driving Downtown - Seattle Washington USA
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Driving Downtown - Tacoma Washington USA
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Bonus: 
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I gotta say, Portland looks amazing. I've never been there, only Seattle/Tacoma/Bellevue, but might be worth a trip.