Marengo Ridge

818 acres | 5 miles of trail

Site Hours
Open Daily Sunrise to Sunset (Some sites are subject to Seasonal Closures or closures due to special circumstances).

2411 N. Route 23, Marengo

Register for a program or event at Marengo Ridge.

Trail Map

Marengo Ridge Conservation Area is one of McHenry County’s most popular and treasured areas. It contains over 818 acres of oak and hickory woodlands interspersed with spruce, aspen, ash and sumac groves.

Hikers can explore 5 miles of trails as they wander through majestic oak woodlands and savanna. The 1.3 mile Kelly Hertel Nature Trail meanders through woodlands and crosses several small bridges that cover ephemeral streams that lace the moraine and drain into the nearby Kishwaukee River. The trail becomes steeper, the woods thicken and the path becomes more twisted. Another route is the 1.1 mile Long Hiking Loop flows into the Kelly Hertel Nature Trail for a combined 2.6 mile hike. The 1.25 mile South Hiking Loop trail travels through restored woodlands and prairie.

In the winter when conditions are right glide through the blanketed woodlands on Cross Country Skis.

For those who enjoy sleeping under the starry skies, Marengo Ridge offers an exclusive use campground for 1 to 100 people. For a frosty winter excursion Marengo Ridge is also open for winter camping from December–March. In addition, Thomas Woods Campground, located on the east side of the site, has another 29 individual tent sites and 18 RV sites that can be reserved.

Marengo Ridge is also a popular area for picnics and group activities. Two picnic shelters or the picnic area can be reserved online or by calling
the District’s Administrative Office. Picnic shelter #2 provides fantastic elevated views of the surrounding area. A fire ring, restrooms and drinking water are also available near the main parking lot.

Night Sky Viewing / Stargazing is allowed from the front parking lots (before the locked gates) by permit only, free of charge, at Marengo Ridge. Call at least 48 hours in advance, or by Thursday at noon for the upcoming Sat./Sun. Call (815) 338-6223, ext. 1211. Permit holders are to stay in the parking lot area; Permit holders need to state their hours of stay. Alcohol is not permited. 

The Marengo Moraine was created about 24,000 years ago by the Wisconsin glacier.  The ridge is made up of rocks, gravel, sand and finer sediments that were carried within or pushed ahead of the ice sheet as it advanced and left behind as it melted.  Where the ice melted and advanced at  an equal rate, the debris piled up at the glacier’s leading edge. The result is a deposit that is up to 280 feet deep, several miles wide and 40 miles long. At its highest point, the ridge stands 1,050 above sea level. In Marengo Ridge Conservation Area, the area around Shelter #2 offers excellent vantage points for surveying the geological history of the area.