Nature Boardwalk at Lincoln Park Zoo transforms an unsustainable urban pond from the 19th century into a rich ecological habitat. With the design’s improvements to water quality, hydrology, landscape, accessibility, and shelter, the site is able to function as an outdoor classroom that demonstrates the coexistence of nature and city. The pond has become a crucial, connective habitat for resident and migratory animal populations, a popular outdoor destination and learning landscape for city residents and visitors alike, and a functional, self-sustaining solution to Chicago’s aging stormwater infrastructure. It helps maintain populations of emblematic animals such as the monarch butterfly and turtles.