1939 Map of Azusa

About this map

The San Gabriel River emerges from the steep canyons of the San Gabriel Mountains into a landscape defined by intensive agricultural and industrial growth in the late 1930s. The region is bisected by the San Bernardino Base Line, with the foothill communities of Monrovia, Duarte, and Azusa serving as hubs for both residence and transit. A complex grid of transportation infrastructure dominates the valley floor, including the Southern Pacific Railroad and the Pacific Electric Railway. Specialized medical facilities such as the Canyon Tuberculosis Preventatorium and a Sanatorium are situated along the base of the mountains, taking advantage of the elevation. The southern reach of the map shows the emerging industrial character of Irwindale and the residential expansion around Margaret Heath School, set against the sprawling washes of Little Big Dalton Wash and Sawpit Wash.