Caddo is an unincorporated community along Alabama State Highway 24 between Decatur and Moulton in Lawrence County, Alabama, United States. Caddo is a feeder community or suburb of Decatur and is part of both the Decatur Metropolitan Area and the Huntsville-Decatur Combined Statistical Area. Movements to incorporate Caddo have been discuss…Caddo is an unincorporated community along Alabama State Highway 24 between Decatur and Moulton in Lawrence County, Alabama, United States. Caddo is a feeder community or suburb of Decatur and is part of both the Decatur Metropolitan Area and the Huntsville-Decatur Combined Statistical Area. Movements to incorporate Caddo have been discussed since the 1980s.