Lowest and Highest Points in Franklin County
Low elevation: <350 feet above mean sea level
Place: Big Muddy River
7.5' quadrangle name: Herrin
PLSS: 3-33-7S-1E
Geology: Cahokia Alluvium and Equality Formation Carmi Member; lake bottom deposits
High elevation: >604 feet above mean sea level
Place: Unnamed hilltop
7.5' quadrangle name: Akin
PLSS: 3-1-7S-4E
Geology: Illinois Vandalia till upland over Pennsylvanian Bond Formation ridge
Area: 427.09 square miles
Total relief (approximate): 254 feet
Average percent slope: .85%
Updated 9/30/2009 JKH