Ralph, SD

ZIP code 57650 serves McIntosh, the county seat of Corson County in north-central South Dakota, and the surrounding rural prairie. Its most prominent landmark is the Corson County Courthouse, a historic civic building in the town center; the Corson County Museum preserves local and regional history. McIntosh is a small service community along U.S. Route 12, with farms and open grassland defining much of the area.