Oregon is awesome and beautiful and there is lots to do here. (Like others have said)
If you're in Portland I agree with Linda, check out Saturday Market (which is also on Sundays), the Pearl district is awesome for galleries and viewing just plain Portland weirdness, the Waterfront is great: you can rent bikes for a very low and reasonable price at Waterfront Bikes and ride the 10 mile loop that is all path, car free -- AWESOMENESS -- you can even go further if you like -- the Springwater Trail will get you about 40 miles of uninterrupted bike trails --
The Portland Art Museum is pretty top notch (in case it's raining while you're here
) Also, if you're here at the end of May there is Rose Festival going on which creates lots of other events all over town.
Forest Park is one of the country's largest urban forests -- it's wiithin Portland. It has excellent trails for running and hiking, it's just plain breathtaking.
Lots of great restaurants: Mothers downtown, Isabel's in the Pearl, Porcelli's in Johns Landing, Andinas, Pazzos, there are so many . . . .
The Gorge is beautiful and a short drive out Hwy 84. Hundreds of very beautiful hikes out there. Angels Rest, Multnomah Falls, Dog Mountain on the Washington side -- hundreds of trails, water falls.
Best beach in Oregon (in my opinion) is Cannon Beach, lovely beach, beautiful views, best coffee in ALL of Oregon at Sleepy Monk in Cannon Beach. They have adirondek chairs outside so you can sit in the sun, enjoy the ocean air and drink the best coffee made by some of the nicest people you will ever meet.
I've lived in Oregon for almost 20 years and it is a wonderful place for anyone, but people who are fitness minded and like to do outside activities are especially happy to be here -- there are tons of things to do at any time of the year and rain does not deter us . . .
I'll probably be back because after I post this I'll think of more things. . .