Yü Wu
Google
I appreciate Springwater Corridor Trail a lot. It's not common to have such a long, continuous, multi-use trail in a big city. There are some auto traffic intersections but at totally acceptable considering how infrequent they are; there are some homeless people and camps as well, but definitely not as bad as some reviews indicated, most are between Bell Ave and 92nd Ave and close to intersections with main roads.
I ran and rode on this trail several times and I found the experiences mostly enjoyable. The scenery changes from time to time, some parts are urban and industrial, some natural and even shaded. I didn't get bored at all running all the way from Portland to to Gresham. You can take this trail to Powell Butte Natural Park, which would make a fantastic long run.