Point Defiance Zoo in Tacoma, Washington is small.
It's sections are arranged in that one can see the whole zoo in a "circle" without having to backtrack.
It took us about 2 hours to see everything at a moderate pace.
The only down-side is that there is limited veiwing area of the animals. For example, you can only see the polar bears from the window although the path leads around the exhibit it is blocked by a big dirt mound. If the walkway was elevated you could get a view from several angles.
It was cool in that there were some cool things I have not seen at other zoos like the Endangered Red Wolf. I had also never seen a tapir up close (they are huge). They also had a pair of baby clouded leopards happily playing. They also have a small, yet well organized aquarium featuring local Washington water habitats and a cool tufted puffin exhibit - very exciting for my sea-bird-loving girl.