Lowest and Highest Points in Calhoun County

Lowest and Highest Points in Calhoun County
Low Elevation: 
<420 feet above mean sea level
Low Place: 
Illinois and Mississippi Rivers
Low Quad Name: 
Grafton
Low PLSS: 
4-6-13S-1E
Low Geology: 
Cahokia Alluvium, river valley
High Elevation: 
>815 feet above mean sea level
High Place: 
unnamed hilltop
High Quad Name: 
Foley
High PLSS: 
4-14-11N-2W
High Geology: 
Providence Moraine, Wisconsin end moraine
Area: 
280.66 square miles
Total Relief: 
395 feet
Percent Slope: 
3.55%