Water, running in what became known as the "Planchas de Plata" canyon southwest of Nogales, flows out of the high country through the area that was called "Arizona" in 1736, past the Arizona Ranch, and joins the Altar River at Saric, Sonora.
Photo by Reba Grandrud
Starting in the mid-1730's, Spanish and Basque prospectors and ranchers started to move into the high and rugged mountainous area south of Tumacácori. Bernardo de Urrea, a criollo Basque born in Culiacán, Mexico started a cattle and horse ranch at the junction of two canyons that flowed in a generally westward direction, which he named Arizona. When he became a deputy chief justice for that area of Sonora, the political jurisdiction also became known as Arizona. When prospective miners developed a Royal Mining Camp called Agua Caliente near Urrea´s ranch, it was sometimes called Agua Caliente of the Arizona [political jurisdiction].