1954 Map of Ontario

About this map

The San Gabriel Mountains dominate the northern landscape, where peaks like Cucamonga Peak and Ontario Peak overlook the rapid post-war development of the Inland Empire. During the mid-1950s, the citrus-growing heritage of settlements like Alta Loma and Etiwanda began transitioning into more industrial and residential roles. The southern portion reveals a dense transportation grid, centered on the Ontario and Upland areas. Critical infrastructure of the era is evident, including the Ontario International Airport and the nearby California Air Nat'l Guard facility. The map captures the complex rail network of the Pacific Electric, Southern Pacific, and Union Pacific railroads, which facilitated both local transit and transcontinental commerce. Educational landmarks such as the Claremont Colleges and Chaffey HS and Jr College highlight the region's growing civic importance as communities like Pomona and Chino expanded across the valley floor.