BAJIO

basin, or plains, region on the Mexican Plateau, west-central Mexico. It is bounded north by the Sierra de Guanajuato, south by the volcanic axis marking the southern edge of the plateau, east by the hills separating the valleys of Celaya and Quertaro, and west by the Sierra de Pnjamo. Occupying southern Guanajuato and northern Michoacn states, the Bajo region ranges in elevation from approximately 5,100 feet (1,550 m) to 5,900 feet (1,800 m) above sea level. The Lerma River and its major tributaries have channeled through lacustrine deposits and volcanic tuff and basaltic rocks separating the series of lakes lying at the foot of the volcanic axis to create a single drainage basin. Fertile soil, temperate climate, and adequate rainfall make the Bajo an important agricultural region, known as the granary of Mexico. Wheat, corn (maize), chick-peas, beans, and various fruits are the principal crops. Numerous cities, including Celaya, Irapuato, Valle de Santiago, and Salamanca, lie in the densely populated Bajo.