​In the late 1800s, the U.S. Army built a wireless communication system across Arizona and New Mexico using reflected sunlight from signal mirrors called heliographs. These networks were established by a remarkable group of young officers—some of whom later rose to the Army’s highest ranks. The heliograph systems proved important in both war and peacetime exercises: they passed information rapidly, were mobile and resource-efficient, and expanded commanders’ ability to maintain control across the vast distances of the Southwest. The image above shows the view to the south from Grand View Peak in Arizona's Pinaleno Mountains. The small white dot is at Bowie Peak.

Mapping Application

My book about the heliograph networks