U.S. Federal Route 65 runs north-south in Central Cerro Gordo County. This is a alternative to Interstate 35. U.S. Rt. 65 passes through the following town in Cerro Gordo County. Mason City U.S. Rt. 65 is multi-plexed in Cerro Gordo County. BUSN U.S. Rt. 18, at Mason City. U.S. Rt. 65 intersects the following highways in Cerro Gordo County. U.S. Rt. 18, near Mason City. BUSN U.S. Rt. 18, near Mason City. Iowa State Route 27, near Mason City. BUSN U.S. Rt. 18, at Mason City. Iowa State Route 122, at Mason City.
