Lakes / Illinois / Perry County / Boulder Lake
Boulder Lake, Illinois
27.92 acres
Surface Area
Where It Sits, and How Deep It Goes
Locator - Illinois
38.02 degrees N, 89.43 degrees W - Perry County. State and county outlines drawn from Census boundary data; the lake marker is placed by its USGS National Hydrography Dataset coordinates, not by eye. Schematic - not a survey map.
How Boulder Lake Stacks Up
- Larger than 8% of the 511 lakes counted in Illinois.
- About 23 miles from Carbondale, as the crow flies.
Lakes Nearby
| Lake | County | Distance | Surface Area |
|---|---|---|---|
| Wesseln Cut | Perry | 1.0 mi | 29.9 acres |
| Pinckneyville Reservoir | Perry | 6.1 mi | 186.56 acres |
| East C Streamline Lake | Perry | 7.6 mi | 131.21 acres |
| West C Streamline Lake | Randolph | 10 mi | 99.34 acres |
| Du Quoin Lake | Perry | 12 mi | 244.39 acres |
| Kinkaid Lake | Jackson | 15 mi | 2,332.92 acres |
Straight-line distance between lake centers.
Facts and Figures
Questions About Boulder Lake
How Big Is Boulder Lake?
Boulder Lake covers 27.92 acres in Perry County, Illinois.
What Is the Largest Lake in Perry County?
Du Quoin Lake is the largest lake in Perry County, at 244.39 acres.
Largest Lakes in Illinois
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Carlyle Lake | Clinton | 22,796.77 acres | - |
| 2 | Mine Number 21 Reservoir | Franklin | 17,062.04 acres | - |
| 3 | Upper Peoria Lake | Woodford | 15,460.64 acres | - |
| 4 | Lake Shelbyville | Shelby | 10,235.1 acres | - |
| 5 | Crab Orchard Lake | Williamson | 7,292.57 acres | - |
All 511 Illinois lakes ranked by surface area
Sources: USGS National Hydrography Dataset (The National Map) lake data (ID 48790768). Verified October 30, 2026.