Janesville is located in Rock County in southern Wisconsin along Interstate 90 on the banks of the Rock River near Beloit. Janesville is known as "Wisconsin's Park Place" or "City of Parks". Its 2,015-acre park system includes 53 improved parks, as well as boat launches, golf courses, and nature trails. This is one of the highest acreages per capita in Wisconsin. A 2006 real estate survey has estimated the population of Janesville, Wisconsin at 62,998.