It’s a big circle going round a laboratory. You don’t get to see the lab much—it’s hidden in the thick forest which includes a healthy strand of tamaracks planted by the Civilian Conservation Corps. It was the CCC that also first built the waterfall at the top of Rocky Glen.
That waterfall was repaired a few years ago by boy scouts and remains one of the more popular features at Waterfall Glen. Named after a trustee with the unlikely moniker of “Waterfall,” this preserve uses 2,689 acres to surround Argonne National Laboratory along the shores of the Des Plaines River.
The main trail of this preserve is an 9 mile long circular route with a screened limestone surface. The area is hilly for Chicagoland and has several large steep hills by local standards. A large part of the trail passes through mature forests, including areas in which non native plants were removed. A large section of the trail passes through a nice section of preserved tallgrass prairie.
It’s also a very popular preserve—on weekends it can be hard to find parking. Parking lots at all three entrances—on the north, east and west sides of the preserve have been observed at capacity parking. The trail can seem somewhat busy due to it’s multi use nature.
Forest Preserve regulations prohibit riding on trails that are less then 8 feet wide. A whole series of trails that are primarily used as pathways for fire control can also be accessed on mountain bikes, though the surface trails are often wet or boggy.
Near the edge of the prairie in the southeast corner of the preserve is a pond that gives some great views of wetland ecology visible from the trail. Unfortunately during wetter seasons the pond floods out a portion of the trail. There is a nearby railroad embankment that can be used to bypass the flooded area.
The northern half of the loop trail also serves as part of the Southeast DuPage Trail, marked as the ‘Waterfall Spur.’ The Southeast DuPage Trail continues west from the parking lot located on the west side of the preserve at Lemont Road.
Directions: Stevenson Highway south to Route 83 South to Bluff Road west.
A map of this forest preserve can be found here.