Lowest and Highest Points in Jackson County

Lowest and Highest Points in Jackson County
Low Elevation: 
<340 feet above mean sea level
Low Place: 
Big Muddy and Mississippi Rivers
Low Quad Name: 
Neelys Landing
Low PLSS: 
3-11-11S-4W
Low Geology: 
Cahokia Alluvium, river valley
High Elevation: 
>811 feet above mean sea level
High Place: 
Grassy Knob
High Quad Name: 
Wolf Lake
High PLSS: 
3-34-10S-3W
High Geology: 
Loess hill over Lower Devonian carbonate bedrock
Area: 
599.01 square miles
Total Relief: 
417 feet
Percent Slope: 
2.25%