Iowa State Route 13 is a north-south artiery on the eastside of the Cedar Rapids Metro Area. Much of IA St Rt 13 in Linn County is a four-lane divided highway. IA St Rt 13 passes through the following towns in Linn County. Cedar Rapids Marion Central City IA St Rt 13 is multi-plexed in Linn County. U.S. Rt. 151, from near Bertram to near Marion.