1898 Map of Mt. Diablo

About this map

The summit of Mount Diablo dominates this late nineteenth-century survey, surrounded by the industrial activities of the Mount Diablo coal field. Distinct mining settlements such as Nortonville, Somersville, and Stewartville are clearly visible, connected by specialized rail lines including the Empire R. R. and the S. P. R. R. San Francisco & New Orleans Line. This map captures the region before the shift from coal extraction to suburban development, showcasing a landscape of steep canyons and ranching valleys like Lone Tree Valley and Horse Valley. To the west, early agricultural centers such as Clayton, Danville, and San Ramon anchor the valleys of Arroyo de las Nueces y Bolbones and San Ramon Valley. The intricate topography highlights local landmarks like the Star Mine and the rugged contours of the Black Hills, documenting the transition from Spanish land grants to industrial enterprise.