Dude, Google Maps. I use it all the time when running my Dark Urban Fantasy game in Seattle ( Sorta a mix of Shadowrun, Dark Conspiracy and Alien Nation using GURPS 4th Ed ) do a screen print of the area you want, import into CC3, and trace, modify as needed
I actually live in Seattle, post if you have questions. Like jsimpson says, use Google maps as a mapping resource. When I want to figure out how to navigate the city I live in, I use Google maps.
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