Lincoln Park Zoo, also known as Lincoln Park Zoological Gardens, is a 35-acre (14 ha) zoo in Lincoln Park, Chicago, Illinois. The zoo was founded in 1868 CE and is the second oldest zoo in the USA. It is also one of a small number of zoos to offer free admission. The zoo is an accredited member of the Association of Zoos and Aquariums (AZA). In 2019 CE it also became an accredited arboretum.
Lincoln Park Zoo is home to a wide variety of animals. The zoo's exhibits include big cats, polar bears, penguins, gorillas, reptiles, monkeys, and other species totalling about 1,100 animals from some 200 species.
The Lincoln Park Zoo was long home to a burr oak tree which was estimated to more than 250 years old.