randymajors.com's Historical County Boundary Maps
An online tool that uses Google Maps to display counties boundaries from ANY HISTORICAL YEAR. Type in ANY PRESENT-DAY PLACE in the U.S. and ANY HISTORICAL YEAR to see the map of county boundaries then in effect, along with all of the current Google Maps places, roads, etc to put the historical map in a current and familiar context! You can then click any county on the map to see the specific history of the boundary changes, and type in different years to see the boundary changes over time. Based on the Atlas of Historical County Boundaries, a project of The Newberry Library.