Lakes / Pennsylvania / Franklin County
Lakes in Franklin County, Pennsylvania
3 lakes counted in Franklin County - the largest is Letterkenny Reservoir at 54 acres.
3
Lakes Counted
54 acres
Largest - Letterkenny Reservoir
Franklin County, highlighted, with its largest counted lakes dotted. Outlines from Census boundary data.
All Counted Lakes
| # | Lake | County | Surface Area | Max Depth |
|---|---|---|---|---|
| 1 | Letterkenny Reservoir | Franklin | 54 acres | None |
| 2 | Mountain Lake | Franklin | 43.7 acres | None |
| 3 | Gunter Valley Reservoir | Franklin | 25.7 acres | None |
Sources: Pennsylvania Fish and Boat Commission lake data; USGS. Verified October 28, 2026.