The North Pond Nature Sanctuary, located in Lincoln Park, is a ten-acre pond that has become an important wildlife area. Historically the site was a dune, then a dumping ground, and an ornamental pond; it was converted in 1999-2000 into a natural area with a littoral zone that greatly improved the water quality by re-establishing native Midwestern ecology. The upland restoration of prairie, savanna, and woodland plants has included only top quality native species such as little bluestem, sky-blue aster, nodding wild onion, side-oats grama, butterfly weed, purple prairie clover, rough blazing star, wild quinine, prairie phlox, coneflowers, false dragonhead, northern prairie dropseed, showy goldenrod, rattlesnake master, shooting star, and wild bergamot. The North Pond Nature Sanctuary is notable as the site where Mayor Richard M. Daley and the US Fish and Wildlife Service signed an Urban Conservation Treaty for Migratory Birds in April, 2004, making the city eligible for federal funds to restore habitat for the lakefront migratory pathway for birds.
Restoration with native plants has drawn a great diversity of wildlife to this urban pond including many species of birds, turtles, frogs, and even a few beavers. Great Blue Herons, Black-crowned Night Herons, Green Herons, Mallards, Wood Ducks, Song Sparrows and woodpeckers can regularly be spotted at the North Pond Nature Sanctuary.
Lincoln Park is a 1,208 acre (488.86 ha) park along the lakefront of Chicago's North Side. It is Chicago's largest public park. Named after Abraham Lincoln, it stretches along the lakeshore for seven miles. With 20 million visitors a year, Lincoln Park is the second most visited park in the United States.