Ciudad Lerdo (syoo-DAHD LER-do), city (1990 pop. 46,593) and township, Durango, N Mexico, in fertile irrigated area, on Nazas R., 4 mi/6.4 km W of Torreón, on Mexico Highways 40 and 49, on RR; 25°34'N 103°30'W. Processing and agr. center (cotton, grain, wine, fruit, vegetables, sugarcane, tobacco); cotton ginning, flour milling, fruit canning, wine and liquor making; foundries. Also Lerdo.