Highways share a common expressway and bypass Ridgeway and Barneveld on the way east into Dane County. In Dane County, US 18 and US 151 bypass Mount Horeb, crossing WIS 78 and WIS 92, and Verona and enter the Madison area, first passing through Fitchburg.
The highways converge on a common route and bypass Ridgeway and Barneveld as they move east into Dane County. In Dane County, US 18 and US 151 go around Mount Horeb, crossing WIS 78 and WIS 92, and Verona before entering the Madison area, initially passing through Fitchburg.