yush!! my idea.. coming to mild fruition!
okay so washington park is NEXT to the zoo, if you wanna drive there the two best routes is off of burnside in sw portland near the zubans... OR taking hwy 26 and getting off at the washington park/zoo exit.. the exit right before the tunnel if your heading into portland, or right after if leaving portland. although i think a much easier route is to take the red or blue line max's to the washington park/zoo stop that is the only one underground, you then take the elevators waaaay up and get off, head right down the road then swing right through the parking lot down the next road, the best spot for pictures is about halfway down (but its soooo worth it) its a bit of a walk for those of you wanting to take the max so bring lotsa water and stuff..
buuut yeah... ask if ya have questions *looks around excitedly*