If you've already worked your way through the Illinois day-hike checklist, this is the list for what comes next. We ranked the state's hardest trails using a composite of difficulty tag (hard or expert), distance, and elevation gain, drawing from the 9,472 mapped Illinois trails in our database. These ten routes are reserved for hikers with the gear, the navigation skills, and the honesty about their own limits to tackle them safely.
Illinois is mostly flat tallgrass prairie reshaped by agriculture — but Shawnee National Forest in the south and the canyon country at Starved Rock are dramatic exceptions. A full River-to-River traverse and serious Shawnee Wilderness routes are the state's tougher objectives. Copperheads in the Shawnee uplands, ticks statewide, and flash floods in slot canyons after thunderstorms.
Our rankings here are data-driven — pulled from the 9,472 mapped entries OutsideAtlas tracks in Illinois — but the data has limits worth being honest about. A composite score weights expert and hard difficulty tags alongside total mileage and elevation gain. The result favors long, vertically aggressive routes with documented technical sections — there are surely tougher off-trail objectives in the state, but those are outside the scope of a trail directory.
The Ranking
Ranked from #1 to #7. Click through any entry for the full trail page — map, elevation profile, weather forecast, and direct OpenStreetMap source link.
#1. r2r guess 27
r2r guess 27 sits near Goreville in Johnson County and is rated expert — our pick for the toughest trail on the list. Tagged expert in OpenStreetMap. Local trail-association reports tend to agree this is one of the better-maintained options in the area, which matters more on a hike of this length than on a quick walk. Best attempted by hikers comfortable with long days, route-finding when the path gets faint, and weather that can turn fast. Not a casual outing. See full trail details, map, and current weather on OutsideAtlas for the most current information.
Open the r2r guess 27 trail page →Map, elevation profile, current weather, and OSM source.#2. R2R ???
R2R ??? sits near Makanda in Jackson County and is rated expert — the #2 entry in a roster of hikes you don't take lightly. Tagged expert in OpenStreetMap. The route is well documented in OpenStreetMap, which is what put it on our radar — community-mapped routes tend to be the ones that get hiked enough to stay open. Best attempted by hikers comfortable with long days, route-finding when the path gets faint, and weather that can turn fast. Not a casual outing. See full trail details, map, and current weather on OutsideAtlas for the most current information.
Open the R2R ??? trail page →Map, elevation profile, current weather, and OSM source.#3. r2r Start E'Town
r2r Start E'Town sits near Elizabethtown in Hardin County and is rated expert — the #3 entry in a roster of hikes you don't take lightly. Tagged expert in OpenStreetMap. It earns its ranking on the data, but trail conditions can change quickly after storms or fire seasons, so verify before you commit a full day. Best attempted by hikers comfortable with long days, route-finding when the path gets faint, and weather that can turn fast. Not a casual outing. See full trail details, map, and current weather on OutsideAtlas for the most current information.
Open the r2r Start E'Town trail page →Map, elevation profile, current weather, and OSM source.#4. Dunes Long Trail Alternates
Dunes Long Trail Alternates sits near Chesterton in Porter County and is rated hard — the #4 entry in a roster of hikes you don't take lightly. Tagged hard in OpenStreetMap. Compared to similar trails in Illinois, this route trades difficulty for either solitude or scenery — sometimes both. Best attempted by hikers comfortable with long days, route-finding when the path gets faint, and weather that can turn fast. Not a casual outing. See full trail details, map, and current weather on OutsideAtlas for the most current information.
Open the Dunes Long Trail Alternates trail page →Map, elevation profile, current weather, and OSM source.#5. Little Grand Canyon
Little Grand Canyon sits near Gorham in Jackson County and is rated hard — the #5 entry in a roster of hikes you don't take lightly. Expect ground surface on a genuinely demanding grade. What makes this one earn its spot on the list is the combination of mapped detail and the kind of through-and-through experience that justifies a longer drive. The natural-surface tread can get slick after rain and muddy in spring — pick a dry weather window if you have the flexibility. Best attempted by hikers comfortable with long days, route-finding when the path gets faint, and weather that can turn fast. Not a casual outing. See full trail details, map, and current weather on OutsideAtlas for the most current information.
Open the Little Grand Canyon trail page →Map, elevation profile, current weather, and OSM source.#6. Little Grand Canyon
Little Grand Canyon sits near Gorham in Jackson County and is rated hard — the #6 entry in a roster of hikes you don't take lightly. Expect ground surface on a genuinely demanding grade. Local trail-association reports tend to agree this is one of the better-maintained options in the area, which matters more on a hike of this length than on a quick walk. The natural-surface tread can get slick after rain and muddy in spring — pick a dry weather window if you have the flexibility. Best attempted by hikers comfortable with long days, route-finding when the path gets faint, and weather that can turn fast. Not a casual outing. See full trail details, map, and current weather on OutsideAtlas for the most current information.
Open the Little Grand Canyon trail page →Map, elevation profile, current weather, and OSM source.#7. Little Grand Canyon
Little Grand Canyon sits near Pomona in Jackson County and is rated hard — the #7 entry in a roster of hikes you don't take lightly. Expect ground surface on a genuinely demanding grade. The route is well documented in OpenStreetMap, which is what put it on our radar — community-mapped routes tend to be the ones that get hiked enough to stay open. The natural-surface tread can get slick after rain and muddy in spring — pick a dry weather window if you have the flexibility. Best attempted by hikers comfortable with long days, route-finding when the path gets faint, and weather that can turn fast. Not a casual outing. See full trail details, map, and current weather on OutsideAtlas for the most current information.
Open the Little Grand Canyon trail page →Map, elevation profile, current weather, and OSM source.Planning your Illinois trip
A few pieces of context are worth keeping in mind specifically for Illinois. Spring and fall are best; summer is muggy and tick-heavy in the south; winter sees ice in Shawnee's sandstone canyons. Copperheads in the Shawnee uplands, ticks statewide, and flash floods in slot canyons after thunderstorms.
Always cross-reference the official land-manager page before driving out — closures, fire restrictions, and seasonal road access can change quickly. Our trail pages link directly back to the OpenStreetMap source so you can see the tags we're working from.
If you're new to hiking generally, our beginner's guide covers footwear, layering, and the day-pack basics. For safety planning on bigger objectives, the ten essentials guide is worth twenty minutes of reading.
More Illinois hiking guides
If you found this useful, the rest of our Illinois coverage continues below.
- Top 10 longest trails in Illinois — Multi-day routes and through-hikes ranked by distance.
- Steepest trails in Illinois — Hikes with the most elevation gain in the state.
- Best beginner hikes in Illinois — Easy, well-marked trails for first-time hikers.
- Best national parks in Illinois — Federal parks and recreation areas ranked.
- Best waterfall hikes in Illinois — Trails leading to named falls, ranked by accessibility.
- Best dog-friendly hikes in Illinois — Where leashed dogs are explicitly welcome.
- Best family hikes in Illinois — Short, easy trails sized for kids and grandparents.
Rankings like this are starting points, not verdicts. Trail conditions change, new routes get tagged, and what was the toughest trail in Illinois last year might not be next year. We refresh these articles when the underlying data shifts meaningfully.
Got a correction, a route we missed, or a question? Drop us a note via the contact page. We read every email and we'd rather hear it from you than miss it.
