Brookfield Zoo a Hillside

Brookfield Zoo is well-known for its extensive use of open-air, unbarred enclosures. Erected in 1934, it created the country's first indoor dolphin exhibit in 1960. Later on, Tropic World, the first indoor rainforest simulation and the world's largest indoor zoo exhibit at the time, debuted in the 1980s. Nowadays, the facility encloses 216 acres, housing approximately 450 species of animals.