Helvetia Half Marathon
The Helvetia Half Marathon happens a little ways outside of Portland but it's well worth the short trip to go run it. Runners of this event can expect some absolutley stunning countryside along the route. We're talking 13 miles (or 10k if you're opting for the shorter version) of Washington/Oregon pasturelands in the middle of June. Glorious! Don't let the sscenery fool you though, the Helvetia Half does pack a bit of a punch by injecting constant hills into the course. You may not PR this one but a little challenge makes the reward that much more worth it!
This event has been pulling in fields of 2,000+ runners, consistently gets voted as the Best Half Marathon in the Northwest, and should definitely be on your list of runs to complete in the area.