The old road, known as the Sonora, Colorado River, or
Southern Emigrant Trail and later as the Butterfield Overland
Mail Route, traversed Box Canyon just east of here. On
January 19, 1847, the Mormon Battalion under the command
of Lieutenant Colonel Philip St. G. Cooke, using hand
tools, hewed a passage through the rocky walls of the
narrow gorge for their wagons and opened the first road
into Southern California.
Marker placed by San Diego County Board of Supervisors and the Historical Markers Committee. Erected 1955.