Jefferson County is located in East Central Missouri. It is named for Thomas Jefferson, one of the Founding Fathers of the United States.
The seat is Hillsboro while the largest city is Arnold. It is bordered by the Mississippi River to the East.
Jefferson County borders St. Louis, Ste. Genevieve, St. Francois, Washington and Franklin Counties in Missouri, as well as Monroe County in Illinois.
Main Highways through the county include I-55, US-61, US-67, MO-21, MO-30 and MO-109.
© Copyright 2010- John Marvig and Contributors. All Rights Reserved