Continuing east, the two routes follow a due-east section of highway, where they pass Earlham. Near the CR F90 / CR P58 interchange, they start heading northeast towards Des Moines. At De Soto, US 6 splits away from I-80 at the interchange with US 169. Tourists who want to see the covered bridges of Madison County (made famous by the book "The Bridges of Madison County") and the birthplace of John Wayne, are directed to follow US 169 south to Winterset. Between De Soto and Van Meter, the Interstate crosses the middle and north branches of the Raccoon River, which converge just south of the crossing of the North Raccoon.