3: St. Louis Zoo, Saint Louis, Missouri
The St. Louis Zoo covers a massive area, but is so well organized that this size hardly matters. Much of the zoo is divided into what St. Louis Zoo refers to as "Zoo Zones," basically different habitats and exhibits. River's Edge is a newer exhibit featuring bush dogs, black rhinos, capybaras, Asian elephants, red river hogs, sun bears, and many, many more. The Discovery Corner is an interactive area full of the Children's Zoo, Monsanto Insectarium, and the Living World, where visitors can discover butterflies, meerkats, goats, fennec foxes, tree kangaroos, insects, guinea pigs, and alpacas.
Address: 1 Government Dr,
St. Louis, MO 63110