The preserve is home to over 740 native plant species, representing roughly 30% of the native flora found in Illinois.
Rocky Glen Waterfall was constructed in the 1930s by the Civilian Conservation Corps using stones salvaged from the foundation of a demolished building.
The site hosts a unique geological feature called the 'ravine ecosystem' which creates micro-climates allowing rare plants to thrive.
Waterfall Glen is one of the largest and most ecologically diverse forest preserves within the DuPage County system.
The land was part of the original site used by the University of Chicago and the U.S. government for the Manhattan Project's nuclear research.
Waterfall Glen Forest Preserve is a 2,492-acre nature area in DuPage County, Illinois, featuring the notable man-made Rocky Glen Waterfall. The preserve is managed by the Forest Preserve District of DuPage County and contains over 11 miles of limestone-surfaced trails. It serves as a biological intersection where tallgrass prairie, oak-maple woodlands, and savanna ecosystems converge. The site is a popular destination for cycling, hiking, and equestrian use, with designated trails for each. A significant portion of the preserve is located on land formerly associated with the Argonne National Laboratory. It offers diverse terrain, including steep ravines and ridges not typical of the surrounding flat landscape. The preserve is designated as a protected conservation area intended to restore native plant and animal habitats.
The wooden observation bridge overlooking the base of Rocky Glen Waterfall.
Bring a printed map or download a digital version, as cellular service can be unreliable in the dense wooded ravines.
Wear sturdy, closed-toe footwear, as the limestone paths can be uneven and accumulate loose gravel.
Carry sufficient water, as there are very few potable water sources located within the interior of the preserve.
Do not attempt to swim in or climb on the Rocky Glen Waterfall, as it is strictly prohibited and dangerous.
Stay on marked trails to protect sensitive restoration areas; dogs must remain on a leash at all times; leave no trace.
