Moraine Hills State Park

By America's State Parks Editorial TeamFebruary 5, 2026 · Updated May 12, 2026

Moraine Hills State Park is a public state park in Illinois near McHenry in McHenry County. It is built around 48-acre Lake Defiance, a kettle lake left by the last glacier and one of the few in Illinois still close to natural.

Quick Facts

Location & Getting There

Moraine Hills State Park is located near McHenry, Illinois. The park’s coordinates are 42.3103, -88.2492.

Things to Do

Moraine Hills is built around a rarity: 48-acre Lake Defiance, a kettle lake left by a stranded glacial ice block, and one of the few glacial lakes in Illinois still in near-natural condition. The IDNR protects it accordingly — bank fishing is prohibited (the peat shoreline is genuinely dangerous) except from the designated piers along the boardwalk, private boats must be car-top only with electric trolling motors, and rentals plus bait are available at the McHenry Dam concession. The park’s western edge runs along the Fox River at the 1934 dam, with a wheelchair-accessible fishing pier and wildlife viewing platforms.

More than 10 miles of trails loop the property, three of them on crushed limestone and all marked for bikes, hiking and skiing: Lake Defiance (3.7 miles), Leatherleaf Bog (3.2), Fox River (2) and the paved River Road Trail (1.7). Two dedicated nature preserves reward the detour — the 120-acre Leatherleaf Bog, a textbook kettle-moraine landscape, and Pike Marsh, home to one of the state’s largest known colonies of pitcher plants.

Best Time to Visit

Roughly half the park’s 2,200 acres are wetlands and lakes, which makes spring and fall migration the show here — the McHenry Dam area draws waterfowl, eagles and birders. Winter turns the trail loops into ski routes. Plan around the firearm deer seasons, when the park closes entirely: the Friday–Sunday before Thanksgiving and Thursday–Sunday after. Hours change seasonally and are posted at the entrance (call 815-385-1624); rangers ask that you’re back at your vehicle 15 minutes before sunset.

Visitor Tips

There are no tickets and no entrance fee — Illinois state parks charge admission nowhere except beach sites, and Moraine Hills has no beach. The one thing to know before packing: this is a day-use park with no campground. The nearest state park camping is at Chain O’Lakes State Park in Spring Grove, with 151 Class A Premium sites ($25/night, $35 on holiday weekends) and 87 Class B sites, reservable at camp.exploremoreil.com — as of August 2026.

The park office sits at 1510 S. River Road, 3 miles south of the city of McHenry in northeast Illinois. Picnic shelters can be reserved through ExploreMoreIL; everything else is first come, first served.

Fees, seasons and closures verified against dnr.illinois.gov on August 29, 2026. Conditions change — confirm before you travel.

Explore More Illinois State Parks

Moraine Hills State Park is one of many outstanding state parks in Illinois. Discover more parks in our Best State Parks in Illinois guide, or use our Park Finder to search by activity, location, or features.

Wildlife & Nature

Moraine Hills State Park — 2,200 acres in McHenry County — preserves a glacial landscape of moraines, kettle lakes, and marshes just 50 miles northwest of downtown Chicago. The park’s Lake Defiance is a glacial kettle lake — formed when a block of glacier ice was buried in sediment, then melted, leaving a basin. The park’s 10 miles of trails wind through fen, marsh, prairie, and oak savanna habitats. Leatherleaf Bog — a state nature preserve — contains sphagnum moss and insectivorous sundew plants typically found hundreds of miles north. Sandhill cranes — 4-foot-tall birds that nearly disappeared from Illinois — now nest in the park’s wetlands. Great blue heron rookeries line the lake. Coyotes, red foxes, and mink are resident.

Nearby Attractions

McHenry County Conservation District manages 25,000+ acres of preserves. Volo Bog State Natural Area — Illinois’ only quaking bog — is nearby. Chain O’ Lakes State Park provides boating on interconnected glacial lakes. Woodstock — the filming location for “Groundhog Day” — has a charming square. Crystal Lake offers suburban recreation. Glacial Park Conservation Area features bog and prairie restoration. Marengo Ridge Conservation Area provides hiking and birding.

Nearby parks: If you have extra time, Volo Bog State Natural Area is a short drive away, and Chain O’Lakes State Park is a short drive away.

About the Author

America's State Parks Editorial Team

America's State Parks is an independent online guide to state parks and other public lands in the United States. Our editorial team compiles park profiles from official agency and operator sources and other identified references, and follows our published editorial policy and review methodology. Where a profile shows a source-check date, that date applies to the detail it names. We correct errors when we find them or when readers report them.

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