Mentioned by Travel Tips - USA Today
Free Chicago Attractions
"The Lincoln Park Zoo is a free family-friendly Chicago attraction and home to hundreds of animals, birds, plants and endangered species from around the globe. Visitors can explore animal exhibits and houses such as the Flamingo Habitat, the Nature Boardwalk, the McCormick Bird House, the Helen Brach Primate House and the Kovler Sea Lion Pool. The venue also serves as a conservation science and research center, and hosts educational programs and workshops that are open to the public."