I joined an event this weekend up in Idaho, just East of Spokane, WA.
If you're looking for a bike outing... and you are willing to make a weekend of it, or even better, a vacation of it, I will highly recommend becoming familiar with the Trails of Coeur d'Alenes. http://friendsofcdatrails.org/
If you think the Rail2Trail between Banks and Vernonia is nice, multiply that by 4 ...and then some. More wildlife, and a scale you can call GRAND, there is 72 miles of trail an a lot of other rides in the region.
The trip is about 400 miles from Portland; the scenery is breath-taking. Just had to provide a shout-out for those looking for a destination.