1898 Map of Mt. Diablo

About this map

Mount Diablo dominates the central landscape of this Contra Costa County survey, surrounded by a complex network of mining settlements and early rail corridors. The northern slopes are defined by the presence of coal mining operations, centered on the clustered towns of Somersville, Nortonville, and Stewartville, which were served by specialized industrial railroads like the Markley Canyon Pittsburg R.R. and the Empire R.R. To the west, the community of Clayton sits at the foot of Mount Zion, while the southern reaches follow the developing agricultural valleys of Danville and San Ramon. The map reveals an era where industrial extraction in the Black Hills and Morgan Territory coexisted with rural ranching in locations such as Lone Tree Valley and Deer Valley. These detailed contours from L.C. Fletcher document the rugged transition from the high peaks to the low-lying Los Medanos and Canada De Los Vaqueros land grants.