Ciudad del Maíz (syoo-DAHD del mah-EES), city (1990 pop. 6,907) and township, San Luis Potosí, N central Mexico, in E outliers of Sierra Madre Oriental, 40 mi/64 km NE of Río Verde; 22°26'N 99°36'W. Corn, wheat, beans, cotton, maguey. Sometimes Maíz.