I visit the Brookfield Zoo quite often to practice my photography. Many of the exhibits use moats to separate the animals from the visitors. This eliminates any obstructions (e.g. glass, wires, cages) which would make creating pictures more difficult. Also, there are several indoor exhibits. This makes the zoo an ideal place for photography even when the weather isn't cooperating.
Tropic World is one of my favorite indoor exhibits. Tropic World is a massive indoor exhibit space that houses a variety of primates. The exhibit is in part lit by a glass ceiling--which provides soft, diffused daylight that is ideal for photography!
An Afternoon Nap
Afternoon nap
Angry Gorilla
Western lowland gorilla
Posed Orangutan
Orangutan
Colorful Character
Colorful character
Silverback
Silverback gorilla