Iowa State Route 188 is a east-west highway in Northwestern Bremer County. This runs from the Bremer/Butler County Line to at junction with U.S. Rt. 63, near Frederika. IA St Rt 188 passes through the following towns in Bremer County. Plainfield Horton IA St Rt 188 is not multi-plexed in Bremer County. IA St Rt 188 intersects the following highways in Bremer County. U.S. Rt. 218, near Plainfield.