Jackson county is 100.6 square miles
Marquette County, Michigan is 3,425 square miles.
Onondaga County, NY is 806 square miles.
Darlington County, SC is 567 square miles.
Lincoln County is 4 831 square miles.
Hennepin County, Minnesota is 606 square miles.
Rockwall County: 129 square miles.
Fulton County, GA's area is 534.75 square miles.
Baldwin County, AL's area is 2,027 square miles.
Loudon County, TN: 247 square miles.Loudon County, VA: 521 square miles.
Fayette County, Tennessee is 706 square miles.
Knox County which has Knoxville as its county seat has an area of about 526 square miles.