The Driftless Area or Paleozoic Plateau is a region in the American Midwest noted mainly for its deeply carved river valleys. It is primarily in southwestern Wisconsin. This region's peculiar terrain is due to its having escaped glacial period. The term "driftless" indicates a lack of glacial drift the material left behind by retreating continental glaciers. Karst topography is found throughout the Driftless area. Karst strains the impurities out of the water and cools it. These cool waters feed springs and cause superb trout habitat. These monolithic giants stand watch over our trout streams and make my home waters the beautiful and pristine area it is.