Low Elevation
< 440 feet above mean sea level
Low Place
Carlyle Lake
Low Quad Name
Keyesport
Low PLSS
3-36-4N-2W
Low Geology
Lake in Kaskaskia River Valley (Cahokia Alluvium in valley)
High Elevation
> 760 feet above mean sea level
High Place
unnamed hilltop
High Quad Name
Fillmore
High PLSS
3-36-7N-2W
High Geology
Hagarstown ridge
Area
378.66 square miles
Total Relief
320 feet
Percent Slope
0.93%