Marengo Ridge

818 acres | 5 miles of trail

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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 permitted. 

Geological History
The major glacial feature at Marengo Ridge Conservation Area is the Marengo Ridge, from which the site derives its name. Left by the retreating Wisconsin glacier, the Marengo Ridge moraine is 40 miles long, 3 miles wide, and creates one of the steepest, vertical moraines in Illinois at 1,050 feet above sea level. The Marengo Moraine was created about 24,000 years ago.  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.  This rugged, fire protected topography supported wooded communities dominated by oak species. The the area around Shelter #2 offers excellent vantage points for surveying the geological history of the area.  

When early settlers came to the area it proved difficult to farm. As a result, numerous blocks of timber were spared and still remain on the landscape. Marengo Ridge Conservation Area protects the larger remaining blocks of what was once the Big Woods of McHenry County, which at one time encompassed large portions of Seneca, Marengo, Dunham and Hartland Townships.

In 1843, Daniel Stewart was the first settler to claim 80 acres in the area. Over the years, the land was primarily used for agriculture. Forty acres of which were planted with a variety of crops such as corn, oats, potatoes and hay. By the late 1920’s, agricultural fields were taken out of production and used as pasture for livestock.

When Dr. Emerson Kunde bought the land in 1950, 40 acres had been heavily grazed by livestock. In an effort to reforest the area, Dr. Kunde planted 15 species of conifers with the hope that they could survive the harsh soil conditions. Although not native to the area, the trees thrived and changed the landscape once again. Over the years, Kunde planted over 10,000 pine trees on 60 acres including Norway spruce, Douglas fir, red and Scotch pine, as well as thousands of wildflowers and hardwoods. In 1974, Kunde sold 80 acres to the Conservation District. In 1977 the District purchased another 40-acre wooded parcel from John Kelly who had operated a private campground on the property. In 1980, the District added the Thomas Woods parcel, which then provided enough space for the District to offer its first recreational campground. Marengo Ridge Conservation Area opened to the public in 1982.