U. S. State County Formation Maps

Each State page contains Animated Rotating Maps showing what year a County was formed and all the County Boundary changes and all the County Boundaries for each census year and for each year overlayed with past and present so you can see the changes in county boundaries.

Alabama (AL) Alaska (AK) Arkansas (AR) Arizona  (AZ) California (CA) Colorado (CO) Connecticut (CT) Delaware (DE) Florida (FL) Georgia (GA) Hawaii (HI) Idaho (ID) Illinois (IL) Indiana (IN) Iowa (IA) Kansas (KS) Kentucky (KY) Louisiana (LA) Maine (ME) Maryland (MD) Massachusetts (MA) Michigan (MI) Minnesota (MN) Mississippi (MS) Missouri (MO)

Montana (MT) Nebraska (NE) Nevada (NV) New Hampshire (NH) New Jersey (NJ) New Mexico (NM) New York (NY) North Carolina (NC) North Dakota (ND) Ohio (OH) Oklahoma (OK) Oregon (OR) Pennsylvania (PA) Rhode Island (RI) South Carolina (SC) South Dakota (SD) Tennessee (TN) Texas (TX) Utah (UT) Vermont (VT) Virginia (VA) Washington (WA) West Virginia  (WV) Wisconsin (WI) Wyoming (WY)