1955 Map of Lone Tree Creek

About this map

The ridge-and-canyon landscape of the Diablo Range comes into focus through this 1950s survey, updated with 1970s aerial data. The map tracks the vital water infrastructure of the Hetch Hetchy Aqueduct as it cuts across the northern edge of the quadrangle. High-elevation terrain is defined by dramatic features like North Ridge, Smiths Ridge, and Pegleg Ridge, revealing a history of mineral extraction and spring-fed hydrology. Mining history is prominent with the Ladd Mine and the Buckeye Mines tucked into the steep drainages. Natural water sources are scattered throughout the canyons, including Lone Tree Mineral Spring, Blue Rock Spring, and Sperry Springs, which often served as critical landmarks for early ranching and prospecting in these dry hills. The intersection of San Joaquin, Stanislaus, and Alameda counties underscores the area's role as a rugged borderland.