Last week, construction crews gingerly maneuvered the poles into a trench dug along the U.S.-Mexico border east of this border town 150 miles west of Tucson.
The poles, known as bollards, are the same height and dark color as the bollards being installed along a 26-mile stretch near San Luis, the border town south of Yuma.
Plans are in the works to spend $646 million on 63 miles of wall in Southern Arizona.
Starting in October, the wall will replace vehicle barriers or shorter fencing along the rest of the Organ Pipe Cactus National Monument near Lukeville and much of the Cabeza Prieta National Wildlife Refuge. The wall also will run along 19 miles in Cochise County and cross the San Pedro River. Another five miles are planned along the Colorado River near Yuma.