Friday, February 12th
On this day in 1871, Maricopa County was created by carving 5.4 million acres (21,850 square kilometers) out of the original four counties: Pima, Yuma, Mohave and Yavapai.
On this day in 1913, the Arizona Mining Engineering Society was announced during a conference at the University of Arizona.
(Photo : Maricopa County, Arizona)