There are roughly 70,000 acres of forest preserve in Cook County, another 26,000 in DuPage, and 31,600 across 65 sites in Lake. You do not need to drive to Starved Rock.
every county opens and closes at a different time, and DuPage's is strange. Cook opens at sunrise. Lake opens at 6:30 a.m. year-round. DuPage opens one hour after sunrise — so if you drive out for a dawn hike in Wheaton the way you would in Palatine, you'll sit in a parking lot watching a locked gate get brighter.
Full rules by county are at the bottom, and read them before you pick a trail.
On this page: Cook County · DuPage County · Lake County · Will County and Midewin · Kane and McHenry Counties · The Rules Change at Every County Line · What's Closed Right Now
Cook County
Over 200 miles of paved trail and nearly 200 unpaved. Open sunrise to sunset, every gate, every day. No admission, no parking fee, anywhere.
Deer Grove, Palatine
~2,000 acres · Yellow loop 5.4 mi · 15.5 mi total
The one most people name first. Five color-blazed trails, including a 2.8-mile paved loop.
Shared with bikers and equestrians, and portions sit low enough to stay muddy for days after rain. The Deer Grove-West lot is on W Dundee Road east of Northwest Highway — not east of Ela Road, which bounds the far west edge and sends you to the wrong place.
Cap Sauers Holding, near Palos Park
1,520 acres · via Sag Valley Yellow loop, 8.1 mi · no lot, no restrooms
Cap Sauers Holding was dedicated as an Illinois Nature Preserve in 1965, fourth-oldest in the state system, with an esker running through it. The district's own description is better than anything we'd write: the center of it is the most remote place in all of Cook County.
Park at Teason's Woods — there's no lot at the preserve itself — and you're sharing gravel with bikes and horses.
Swallow Cliff Woods, near Palos Park
100-ft bluff · 125 + 168 limestone stairs · no dogs on the stairs
Swallow Cliff Woods is an outdoor stair gym with a forest attached, and it is not a quiet hike. The stairs climb the old toboggan run, and a second set added in 2016 makes a circuit. It feeds the Sag Valley (20.4 mi) and Palos (42.1 mi) unpaved systems if you want to keep going.
Their signage credits the CCC with building the stairs in 1930, which is three years before the CCC existed.
Thatcher Woods, River Forest
245 acres · 4.9 mi, foot traffic only
No bikes, no horses — Thatcher Woods is the rare Cook County preserve designed around people on foot, with a free year-round museum at the trailhead. The catch is in the district's own wording: some areas flood in spring and summer. And it's hemmed in by village streets, so you're never far from a car.
Camp Sagawau, Lemont
2.6 mi · guided access only
Camp Sagawau's canyon holds the only natural exposure of bedrock in Cook County. Individual entry is restricted to protect the site, so you go on their schedule or not at all. In winter the trails become groomed ski track with walkers prohibited outright — the opposite of what you'd assume.
Little Red Schoolhouse, Willow Springs
~2.5 mi total · closed Fridays · no dogs
One correction first, because half the internet puts this in Palos Hills: it's at 9800 Willow Springs Road. And there is no three-mile loop — Black Oak is 1.3, White Oak 0.7, Farm Pond 0.4, plus a paved accessible trail just under half a mile.
Hours run 8–5 March through October and 8–4 the rest of the year, not sunrise to sunset like the rest of the county.
Salt Creek Trail System, western suburbs
16.4 mi, mixed surface · Bemis Woods-South to the Chicago Portage
The Salt Creek Trail runs along the Des Plaines and Salt Creek past Brookfield Zoo, reaching the DuPage line at its west end. Good news for anyone who gave up on it: the I-294 underpass at Bemis Woods fully reopened July 13, 2026, after the multiyear tollway rebuild.
One to skip if you're hiking: Busse Woods is a 12.9-mile paved multi-use loop with heavy bike traffic and tollway noise. Go for the 17-acre elk pasture, which has had a herd since 1925. Not for the walk.
Cap Sauers for solitude, Swallow Cliff for a workout, Thatcher for a foot-only walk, and check the address before Little Red Schoolhouse.
DuPage County
26,000 acres, 60 preserves, more than 175 miles of trail — plus over 80 miles groomed for cross-country skiing, which is more than anyone else here does.
Waterfall Glen, Darien
2,503 acres · main loop 9.5 mi limestone
Wrapped around Argonne National Laboratory, with almost 11 miles total across four trails. The waterfall is real but modest — a Civilian Conservation Corps structure at Rocky Glen, not a cataract.
Parking is the detail most guides get wrong. The lots are on Northgate Road a quarter mile west of Cass Avenue, on Bluff Road three tenths east of Cass, and on Lemont Road at 101st. Bluff Road is reached via Cass; it isn't a second entrance off it.
Blackwell, Warrenville
1,366 acres · 7.7 mi, six trails · genuine hills
Connects to both the Illinois Prairie Path Aurora Branch and the DuPage River Trail, which makes it the best place here to string together a longer day.
Mount Hoy is a former landfill, and the record is specific: 40 acres, accepting waste 1965–1973, rising about 150 feet, delisted from the Superfund National Priorities List in September 2020. You climb a closed dump for the best view in the county, and it's a good view.
Before you go: utility work on Mack Road between Williams Road and Route 59 is still causing intermittent detours. It affects road access to the McKee Marsh lot, the off-leash area and the canoe launch — not the trails.
Greene Valley, Naperville and Woodridge
1,388 acres · 13.8 mi · overlook open weekends May–Oct only
Greene Valley's 190-foot scenic overlook is the reason to come and is almost never open: weekends only, May through October, one hour after sunrise to 6 p.m., weather permitting — and the district says outright it may close during those hours without notice for Illinois EPA work. Check before you plan around it.
Pratt's Wayne Woods, Wayne
Largest in the district · 12+ mi
The Prairie Path's Elgin Branch runs through Pratt's Wayne Woods, along with five water bodies and the 256-acre Brewster Creek Marsh Nature Preserve. Heavy equestrian use chews up the turf sections after rain.
We're not printing an acreage. The district's own page gives two different numbers in two places.
Herrick Lake, Wheaton
887 acres · 7+ mi · busy
Herrick Lake carries the nationally designated Danada–Herrick Lake Regional Trail and links a roughly 3,700-acre chain of connected preserves. Shared with bikes and horses, so it isn't where you go for solitude. The lake is also one of the county's better shore fishing spots.
McDowell Grove, Naperville
465 acres · ~7 mi, turf and limestone · floodplain
McDowell Grove was a CCC camp in the 1930s, later a WWII radar and OSS training site, along the West Branch of the DuPage. Being floodplain, the turf sections flood and stay muddy longer than you'd expect.
Hidden Lake, Downers Grove
390 acres · 2 mi · hiking and jogging only
No bikes, no horses, which is rarer than it should be. Two lakes and a stretch of the East Branch. Entry is on the east side of Route 53, a quarter mile south of Butterfield.
Fullersburg Woods in Oak Brook gets a mention with a warning: a habitat project is causing temporary trail closures, posted on signs as they happen.
Waterfall Glen is the marquee loop, Blackwell is the connector for a long day, and Hidden Lake is the quiet one nobody shares with a bike.
Lake County
More than 200 miles across 65 sites. Most trails are 8 to 14 feet of gravel, which the district counts as an accessible surface. Six preserves have paved accessible trails: Fort Sheridan, Hastings Lake, Independence Grove, Old School, Ryerson, and the Millennium Trail between Singing Hills and Kestrel Ridge.
Captain Daniel Wright Woods, Mettawa
750 acres · 4 mi
A short loop around a pond plus a 3-mile loop shared with bikes, skiers and horses. There's a wheelchair-accessible fishing pier on the pond, and a footbridge over the Des Plaines connecting to Half Day Forest Preserve.
Old School, Mettawa
Loops of 1.22, 1.5 and 2.6 mi · solar-lit until 9 p.m. in winter
One of the six paved preserves, one of the plowed ones, and its trail is lit from early November to mid-March — one of very few places in the region you can legally walk a trail after dark in winter. The downside is permanent: I-94 runs the boundary, and you hear it.
Ryerson, Riverwoods
561 acres · boardwalk and paved trail · no dogs, no bikes off the roads
Des Plaines floodplain forest, dedicated as an Illinois Nature Preserve, and exactly because of the restrictions it's the quietest walking in the district. Two caveats: it floods, and there's active construction whose scope and dates we couldn't confirm. Call before driving out.
Middlefork Savanna, Lake Forest
670 acres · 4.5 mi in short segments
Protects a globally rare black-soil tallgrass savanna, twenty-five miles from the Loop. An active Metra line cuts through it, and the grass sections hold water.
Grant Woods, Lake Villa and Ingleside
1,070 acres · 6 mi gravel
Some routes are designated for snowmobiles in winter, which changes the experience considerably.
Will County and Midewin
Will County sets hours per preserve rather than district-wide — some open at 8, some at sunrise, all close at sunset. Parking is always free.
Midewin National Tallgrass Prairie, Wilmington and Elwood
~30 mi of trail · federal, not county · bison
The only national tallgrass prairie in the country, run by the US Forest Service. About 22 miles shared-use and 8 hiking-only, on mowed turf and gravel service roads. Its own sources disagree on the total — one says 30 miles, another over 34 — so treat exact figures with suspicion.
The bison viewing is open: park at the Iron Bridge trailhead for a 3-mile round trip to the Southwest Bison Overlook, which has benches and spotting scopes. The Forest Service is clear that sightings aren't guaranteed, and we're not printing a herd count because no agency publishes one.
The real warnings are water and shade: there is no water anywhere except the Welcome Center, and there's almost no shade. Bring more than you think. The Blodgett Marsh bridge is closed and the Henslow trail rerouted, no timetable given.
Messenger Woods, Homer Glen
1.87 mi inside the nature preserve, 1.36 outside
Messenger Woods is regionally known for its spring wildflower carpet — in April and May it's one of the best walks in the county. The rest of the year it's a short, muddy floodplain loop.
Hickory Creek, New Lenox and Mokena
1.71 mi of dirt hiking
Read Hickory Creek's numbers carefully — the other six miles inside the preserve is paved bikeway shared with cyclists. It holds the largest Illinois population of the state-threatened savanna blazing star. The LaPorte Road flooding alert we tracked now 404s, so its status is unconfirmed.
Two to avoid right now. Thorn Creek Woods has an indefinitely closed pedestrian bridge, three trails shut, only the half-mile Nature Center Loop open, and a flat dog ban. Lake Renwick's Heron Rookery closes March 1 through August 15 every year for nesting; it reopens August 16.
Kane and McHenry Counties
Both open sunrise to sunset. Kane requires leashes everywhere, with off-leash areas at three preserves. McHenry caps leashes at 10 feet and has no off-leash areas at all. Neither publishes a day-use fee.
Big Rock, Kane County
840 acres · 10.12 mi, mostly mowed
Big Rock's draw is Siegler Lake, a 32-acre flooded limestone quarry 65 feet deep. The 3-mile Northwestern Lot Line Trail is flat, shadeless mowed grass, and equestrians share the network.
LeRoy Oakes, St. Charles
459 acres · 9.07 mi · eastern trailhead of the Great Western Trail
The 1843 Durant House is on site at LeRoy Oakes. Mostly mowed grass, so the district warns trails may close outright in wet weather.
Johnson's Mound, Elburn
2.64 mi on a kame
Johnson's Mound is a stratified glacial gravel hill with about 50 feet of relief, dedicated as an Illinois Nature Preserve. An unusual landform and a 45-minute stop, not a hiking day — the mileage is short overlapping loops.
Glacial Park, Ringwood
3,439 acres · 5 mi trail + 4.78 mi horse trail
The best glacial terrain in the region, if you're precise about what that means: the delta kames are the gravel hills you climb, the kettles are the wet basins between them, and one kettle holds a 10-acre leatherleaf and sphagnum bog. It is not a Wisconsin-style kettle moraine, whatever the listicles say.
The kame-top prairie is shadeless, the kettle wetlands breed mosquitoes, and the horse trails are currently on a Harts Road detour.
Marengo Ridge, Marengo
818 acres · 7.65 mi
Marengo Ridge is oak-hickory on one of the steepest vertical moraines in Illinois. Route 23 frontage and an on-site campground mean engine noise, and the wooded trails hold mud.
The Hollows, Cary
4.75 mi · fronts US-14
The Hollows includes a one-mile paved accessible path to a fishing pier. Plan on road noise throughout.
The Rules Change at Every County Line
- Hours. Cook: sunrise to sunset, every gate, every day. DuPage: one hour after sunrise to one hour after sunset, and the gates follow the ordinance exactly. Lake: 6:30 a.m. to sunset year-round. Kane and McHenry: sunrise to sunset. Will: varies by preserve. Cook's nature centers are their own exception — 8 to 5 in summer, 8 to 4 in winter, closed Fridays.
- Dogs. Leashed everywhere, but the bans matter more than the rule: none at all at Cook's nature centers, Lake County's Ryerson and Independence Grove, or Will County's Thorn Creek Woods. DuPage says dogs are welcome at most preserves without publishing which ones aren't. McHenry caps leashes at 10 feet, no off-leash anywhere.
- Money. Cook, Will, Kane and McHenry: free to enter and park. DuPage: no fee we could find stated, though no page says "free" in those words. The only regular charge in six counties is non-resident parking at Lake County's Independence Grove, spring through fall — $6 a car Monday to Thursday, $12 Friday through Sunday. Residents park free.
- Off-leash permits, DuPage. Seven preserves, permit required: $60 a year for residents, $170 non-resident, day permits $12 and $20.
- Winter. Cook deliberately does not plow or salt its trails — the stated reason is keeping salt runoff out of natural areas — so a Cook trail in January is whatever the last person's boots made of it. Lake plows the paved loops at exactly three preserves: Hastings Lake, Independence Grove and Old School. Ryerson is not one of them; the district preserves snow there for skiing. DuPage grooms 80-plus miles for cross-country. A maintained winter walk means a Lake County trip.
Takeaway: the county line changes the hours, the dog rules and the winter maintenance. Check which county you're driving to before you set an alarm.
What's Closed Right Now
Re-verified against each district's own alerts on August 13, 2026. Closures move faster than any list can, so check Cook's live alerts page before you drive. It changes weekly, and it is where the storm closures below will vanish from first.
- Des Plaines River Trail (Cook), Lawrence to Irving Park: fully closed through fall 2026
- Busse Woods Red Paved Loop: repairs through September 30; Midlothian Meadows paving into September
- Poplar Creek Red Paved Loop, Barrington Rd at Golf Rd: closed for IDOT work into early fall. Detour east of Barrington Road
- Swallow Cliff-North: Thursday maintenance through November 30; the lot may open late
- Blackwell (DuPage): Mack Road utility work, road access only
- Fullersburg Woods (DuPage): habitat project, closures posted on site
- Thorn Creek Woods (Will): the Thorn Creek footbridge plus the Woodland, Owl Lake and Wetland trails, all closed until further notice. The Nature Center Loop is open
- Midewin: Blodgett Marsh bridge closed, Henslow rerouted, no timetable
- Lake Renwick (Will): the Heron Rookery is closed March 1 to August 15 every year for nesting, and reopens August 16. This does not close the preserve — Copley Nature Park and Turtle Lake Access stay open 8 a.m. to sunset year-round
- Glacial Park (McHenry): the horse trail is closed on a Harts Road detour. Walking trails and all lots are open
- Reopened: the North Branch Trail between Forest Glen and Central is open again, and so is the Salt Creek Trail's I-294 underpass at Bemis Woods
Storm damage, and the shortest-lived thing on this page: as of August 13 a run of south-suburban Cook lots are shut for debris through roughly August 17: Glenwood Woods, Sauk Trail Woods, Lansing Woods, Jurgensen Woods, North Creek Meadow, Brownell Woods and Bobolink among them. In Will County, Lockport Prairie is closed for a downed power line and the Plum Creek Greenway "Big Bridge" has been out since July 27. Those first ones should be gone by the time you read this; the live pages will say.
Cook will let you in at first light, DuPage will make you wait an hour for it, and the gate does not care that you looked up the hours for the wrong county.
This guide is part of The New Parent's Suburban Starter Pack.