Jefferson County, Kansas

Jefferson County (county code JF) is a county in the U.S. state of Kansas. In 2010, 19,126 people lived there. Its county seat is Oskaloosa. Its biggest city is Valley Falls.
Geography.
The U.S. Census Bureau says that the county has a total area of . Of that, is land and (4.3%) is water.
People.
Jefferson County is included in the Topeka, KS Metropolitan Statistical Area.