Wisconsin uses letters as route designations for its county roads. Routes may be labeled with a single letter (CTH-H), double letter (CTH-LL or CTH-AB) or triple letter (CTH-BBB). Roads are usually named sequentially, though there is leeway to have the letter designation stand for the initials of a road, geographical feature, political division (such as CTH KR along the Kenosha/Racine county line) or in honor of a person. [1]
Route designations may or may not be repeated within a single county, mostly depending on the size and population of the county. Designations also may or may not continue over a county line. Usually the letter designation remains the same when the route is a former Wisconsin state highway that has been decommissioned and turned over to county control. There is no east/west or north/south pattern restrictions on which letters can be used for a road, and they can be looped around counties and metropolitan areas.