How far is Lake Forest, IL from Decatur, IL?
The driving distance from Lake Forest, IL to Decatur, IL is about 204.9 miles (329.7 km), with a travel time of about 03h 31m by car.
- The straight-line flight distance is about 176.9 miles (284.7 km).
- For a round trip, plan for roughly 07h 02m of driving time before adding stops, traffic, or weather delays.
- A comfortable departure window is usually 6:00 AM to 8:00 AM CDT.
Reverse, save, or send this route
This drive is better planned with a longer stop or an overnight stay. Copy the route link, send it to another device, or print a clean version before you head out.
This drive is better planned with a longer stop or an overnight stay.
Flight Distance
Driving Distance
Gas Cost Calculator
Leave and Arrive Planner
Pick a departure time to see your estimated arrival and same-day return window.
Drive time stays fixed at 03h 31m.
An early departure helps you fit a real stop into the day without turning the return into a late-night drive.
You are leaving earlier than the recommended window, which gives you extra margin for breaks and traffic.
Halfway Point
A useful midpoint for breaks, coffee, or meeting in the middle.
Village in Illinois
Route Weather Snapshot
Check the forecast at both ends before you head out.
Mostly Sunny
Partly Sunny
Driving Route Map
The map below follows the saved road route between Lake Forest and Decatur.
Turn-by-Turn Driving Directions
Step-by-step road directions between Lake Forest and Decatur.
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1
Start on Griffith Road
22 m · 3 sec · Griffith Road
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2
Turn straight onto East Woodland Road
1960 ft · 1 min · East Woodland Road
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3
At the end of the road, turn left onto North Green Bay Road
2060 ft · 1 min · North Green Bay Road
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4
Turn right onto East Deerpath
1.6 km · 3 min · East Deerpath
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5
Take the ramp left toward Deerpath Road
1302 ft · 36 sec
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6
Merge slight left onto South Skokie Highway
926 ft · 12 sec · South Skokie Highway
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7
Take the exit slight right toward IL 60
534 ft · 14 sec
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8
Continue on W Kennedy Road
2279 ft · 45 sec · W Kennedy Road
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9
Continue on Townline Road
1.5 km · 2 min · Townline Road
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10
Continue on East Townline Road
1.1 km · 1 min · East Townline Road
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11
Take the ramp left toward I 94 Toll East: Indiana
1872 ft · 49 sec
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12
Merge slight left onto Tri-State Tollway
5.8 mi · 7 min · Tri-State Tollway
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13
Keep slight right to continue on Tri-State Tollway
22.7 mi · 29 min · Tri-State Tollway
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14
Keep slight left to continue on Tri-State Tollway
4.8 mi · 6 min · Tri-State Tollway
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15
Keep slight right to continue on Tri-State Tollway
1.2 mi · 1 min · Tri-State Tollway
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16
Take the exit slight right toward I 55: Chicago, St. Louis
1 km · 1 min
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17
Keep slight right to continue on I 55 South: Saint Louis
2295 ft · 56 sec
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18
Merge slight left onto Adlai Stevenson Expressway
119.4 mi · 2 hr 13 min · Adlai Stevenson Expressway
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19
Keep slight left to continue on I 74 East, US 51 South, US 55 Business North: Indianapolis, Decatur
2.1 mi · 2 min
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20
Take the exit slight right toward US 51 South, US 51 Business North: Decatur, Bloomington
1616 ft · 40 sec
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21
Continue on North 1450 East Road
14.7 mi · 18 min · North 1450 East Road
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22
Continue on North Walnut Street
23.2 mi · 30 min · North Walnut Street
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23
Turn straight
4.7 mi · 8 min
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24
Turn left onto East Wood Street
91 m · 8 sec · East Wood Street
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25
Arrive at your destination
0 m · 1 sec · East Wood Street
Car Route Details
A richer read on the saved driving route between Lake Forest and Decatur.
Highway-focused drive
Most of the mileage stays on named highways, so the important moments are ramps, exits, merges, and the final local approach.
Adlai Stevenson Expressway
Merge slight left onto Adlai Stevenson Expressway
119 mi · 02h 13m
Route Summary
A quick read on whether this route feels easy, ambitious, or worth planning around.
A longer out-and-back drive
This is still possible in one day, but it becomes a long driving day. Leaving early and planning your stop window matters more here.
Mostly Sunny leaving Lake Forest and Partly Sunny near Decatur.
Trip Questions
Direct answers travelers usually want before committing to the drive.
How long does it take to drive from Lake Forest to Decatur?
The road trip is about 204.9 miles (329.7 km) and usually takes 03h 31m in normal driving conditions.
Is this a same-day trip or an overnight route?
This is still possible in one day, but it becomes a long driving day. Leaving early and planning your stop window matters more here.
What is the halfway point on this route?
Dwight is a useful midpoint, sitting about 102.3 miles from Lake Forest and 102.5 miles from Decatur.
How much longer is the road route than the straight-line distance?
The direct path is about 176.9 miles (284.7 km), while the road route adds roughly 28 extra miles because roads do not follow the straight air line.
When is the best time to leave for this route?
A good departure window is usually 6:00 AM to 8:00 AM CDT. If you want a more comfortable same-day return, try to leave by 9:58 AM CDT.
How much will gas cost for this route?
Using about 28.3 MPG, regular gas is estimated at $27.26 one way or $54.53 round trip. Estimated CO2 is about 64.3 kg one way.
What should you check before leaving?
Before you leave, expect Mostly Sunny around Lake Forest and Partly Sunny near Decatur.
Stop Ideas Near Dwight
Useful break, food, and waypoint ideas within about 15 miles of the route midpoint.
Transit and Meeting Points
Useful pickup, handoff, or rendezvous points close to Dwight.
Dwight station
Pontiac station
Kankakee
Gilman
Flight Path Map
This map shows the direct air route between Lake Forest and Decatur. Straight-line distance: 176.89 mi (284.67 km).
#1 Lake Forest
City in Lake County, Illinois, United States
| Population | 19,379 |
| Coordinates | 42.2586300, -87.8406300 |
| Altitude | 210 |
| Country | United States |
#2 Decatur
The most populous city in Macon County, Illinois.
| Population | 70,007 |
| Coordinates | 39.8403100, -88.9548000 |
| Altitude | 205 |
| Country | United States |
End: East Wood Street (-88.954801, 39.840341)
Estimated Travel Time
Distance: 330 km by road
| Speed | Time |
|---|---|
| 30 mph (48.3 km/h) | 06h 49m |
| 40 mph (64.37 km/h) | 05h 07m |
| 50 mph (80.47 km/h) | 04h 05m |
| 60 mph (96.56 km/h) | 03h 24m |
| 70 mph (112.65 km/h) | 02h 55m |
| 80 mph (129 km/h) | 02h 33m |
Fuel, Round Trip and CO2
Estimated fuel cost and emissions for this route.
| Fuel | $/gal | One way | Round trip |
|---|---|---|---|
| Regular gas | $3.77 | $27.26 | $54.53 |
| Mid-grade | $4.25 | $30.75 | $61.50 |
| Premium | $4.65 | $33.65 | $67.30 |
| Diesel | $5.30 | $38.35 | $76.70 |
Assumes 8.3 L/100 km (about 28.3 MPG). CO2 is an estimate and varies by vehicle, fuel blend, traffic, and terrain.
Prices in Illinois · May 30, 2026
Distance to Other Cities
Planning a road trip? See the full trip guide on Trip.ovh — stops, fuel costs, weather, and departure timing.