There are two counties in the United States known as Hillsborough. Hillsborough County, Florida covers a total area of 1,266.22 square miles (3,279 square kilometers); and Hillsborough County, New Hampshire covers a total area of 892 square miles (2,310 square kilometers).
The largest County in Maine is Aroostook, measuring 6,829 square miles.
Putnam County, Florida has a total area of 827 square miles.
Approx 20105 square miles.
Idaho County is 8,502 sq miles (22,020 km²).
Harney County, OR is 10,226 sq miles (26,485 km²).
There are 2,569 square miles in Lincoln County, Nevada.
The smallest county in Texas is Rockwall County, which is about 147 square miles in size.
Jackson County in Florida covers approximately 917 square miles.
Onondaga County, NY is 806 square miles.
Marquette County, Michigan is 3,425 square miles.
Darlington County, SC is 567 square miles.
Hennepin County, Minnesota is 606 square miles.
Tillamook County, Oregon is 1,133 square miles.
Fulton County, GA's area is 534.75 square miles.
Baldwin County, AL's area is 2,027 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.