 When the Iowa primary highway system was created in 1920 , Primary Road No. 56 extended from West Union eastward to Guttenberg . It began in a different location in West Union than it does today , beginning at Primary Road No. 19 in the northeastern part of town . The route then headed south along Pine Street . In Elkader , Primary Road No. 56 joined Primary Roads No. 10 and No. 13 and crossed the Turkey River on the Keystone Bridge . Shortly after leaving Elkader , Primary Road No. 56 split away from the other two routes and headed east . It turned south at Primary Road No. 20 and the two routes headed to Guttenberg . The Primary Road No. 56 designation ended in Guttenberg . 
