From my suggestion in USAToday‘s feature: 51 Great Places to See Wildlife
Bald eagles, white pelicans and trumpeter swans fly through Illinois along their highway, the Mississippi River, throughout the year. The Riverlands Migratory Bird Sanctuary in Alton offers birders their best bet for seeing and learning about flocks on the flyway. Trails snake throughout the wetland sanctuary, which is open year-round and is free. Look for a new Audubon Center with nature center and riverboat, scheduled to open next spring.
