The Coulee Region, as it is colloquially known (officially designated the Driftless Area by the USGS and popularly referred to as the Driftless Zone, or Driftless Region since the 1980s) is an area of about 20,000 square miles (52,000 km²) in western Wisconsin, northeastern Iowa, southeastern Minnesota, and extreme northwestern Illinois, which was by-passed by the last continental glaciers.

As a result, the topography is more rugged than that usually associated with the Midwest. In Wisconsin, the region parallels the Mississippi River to the Illinois state line in a band 60 to 80 miles (100 to 130 km) wide. About halfway a lobe extends farther northeast into Wisconsin. In Iowa, it also runs parallel to the Mississippi River from the Minnesota state line to about Dubuque in a band approximately 20 miles (32 km) wide. The Minnesota and Illinois portions are much smaller, by comparison, and much more irregularly defined.

Map of the Upper Midwest, showing Driftless Zone

Other than rugged topography, the Coulee Region has no one single unity of landscape. In the north there is a "North Woods" visual appearance, as much of the terrain is covered in deciduous forest. The Dells of the Wisconsin River, along the route of the Wisconsin River, in the bed of Glacial Lake Wisconsin, are a unique and specially formed scenic attraction in their own right. In southwestern Wisconsin there is a more pastoral, semi-wooded landscape with many prosperous farms along rural by-ways. The portion of the Mississippi River that flows through the region is noted for its high bluffs and dramatic river scenery. In Iowa, it takes the appearance of low rugged hills covered with pine woods, a landscape not usually associated with that state. In Illinois, the area contains Charles Mound, the highest point in that state.

Early European settlers derived the name Coulee Region from the French word "couler," which means "to flow." The term is now usually used when referring only to the hilly parts of the region, while Driftless Zone may imply flatter areas such as those found around Glacial Lake Wisconsin.(From Wikipedia)

See Also TU DARE report: "Driftless Area, Land of Opportunity" Printable Version(opens in new window)