Facts about Rock County, Wisconsin
Rock County is a county in the U.S. state of Wisconsin. As of the 2010 census, the population was 160,331. Its county seat is Janesville. Rock County comprises the Janesville-Beloit, WI Metropolitan Statistical Area and is included in the Madison-Janesville-Beloit, WI Combined Statistical Area.
GeographyAccording to the U.S. Census Bureau, the county has a total area of 726 square miles (1,880 km²), of which 718 square miles (1,860 km²) is land and 8.0 square miles (21 km²) (1.1%) is water.
DemographicsAs of the census of 2000, there were 152,307 people, 58,617 households, and 40,387 families residing in the county. The population density was 211 people per square mile (82/km²). There were 62,187 housing units at an average density of 86 per square mile (33/km²).
Serving Rock County, Wisconsin

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