Iowa - State Highway 1
Iowa City. The backs of the infinitely durable cast-iron shields were reused to create retroreflective markers in the late 1940s and 50s.
Photo by Jim Lindsay - 04/26/76
Iowa City. The backs of the infinitely durable cast-iron shields were reused to create retroreflective markers in the late 1940s and 50s.
Photo by Jim Lindsay - 04/26/76