Is the Wisconsin-Illinois Boundary a Straight Line?

The Wisconsin-Illinois boundary should be a straight line. But it is not. Find out why.

How Wisconsin’s Counties Got Their Shapes

Wisconsin’s county boundaries have attained their current shapes as a result of numerous boundary changes that date back to the formation of Wisconsin Territory in 1836.

State Boundary Data

There are various sources for Wisconsin state boundary data, but quality levels can be quite variable. In addition, most state boundary representations are generalized and will not necessarily match other features, such as hydrography, at the very largest map scales.

Wisconsin Outline Maps

We offer a variety of digital outline maps for use in various graphics, illustration, or office software. The map graphics available for download have been derived from several common layers of digital GIS data. All of the statewide GIS data layers used were processed by state agencies and exist in the Wisconsin Transverse Mercator coordinate system.