Loading map...

1903 Map of San Antonio

Name: 1903 Topographic Map of San Antonio
Creator: U.S. Geological Survey
Published: 1943
License: https://creativecommons.org/publicdomain/mark/1.0/

USGS Topo · Published 1943

About this map

San Antonio Peak (Mt Baldy) serves as the dramatic anchor of this high-altitude survey, where the steep southern slopes of the San Gabriel Mountains meet the high Mojave Desert. The landscape is dominated by the massive tectonic scarring of the San Andreas Rift Zone, which carves a distinct northwest-southeast path through Lone Pine Canyon and into the Swarthout Valley. This rift creates a visible Watershed Divide, separating the drainages of the Great Basin Pacific systems.

Evidence of early exploration and resource extraction appears near Vincent Gulch, where a mine is tucked into the northern ridges. The drainage patterns of the San Gabriel River headwaters, including Iron Fork and Fish Fork, reveal the deep erosion around Iron Mt. High-ridgeline features like the Devils Backbone and Telegraph Peak highlight the difficult terrain managed by the Angeles National Forest and San Bernardino National Forest at the turn of the century.