This zoological is decades ahead of any other zoo I have visited, including the zoo in San Diego. The St. Louis Zoo has do a fantastic job in designing a park that reflects a more natural setting for the animals and, also, developed a large number of interactive events and areas for park patrons. The staff is knowledgeable, professional and very friendly, and the park it self is beautifully landscaped, well shaded, and impeccably maintained. Amenities abound for visitors, and you can even bring in your own lunch, if you prefer. All of this, and the admission price is $0.
Pros: parking, location of park, no admission costs
Cons: amenity prices high