1983 Map of Thumb Peak

About this map

The Bradshaw Trail traverses this high desert terrain in the early 1980s, marking a historic route through the gap between the Mule Mountains and the northern reach of the Palo Verde Mountains. This area, characterized by the broad Palo Verde Mesa and numerous seasonal drainages like Sand Wash and Dry Wash, reveals a landscape of industrial extraction and natural landmarks. Local prospectors and historians can identify the Open Pit Mine near Opal Hill, as well as a Borrow Pit further north. Notable geographic markers include the distinctive Thumb Peak and the vital water source at Clapp Spring. The boundary between Riverside Co and Imperial Co bisects the quadrangle, which is also dominated by infrastructure such as the Doublewood Pole Powerline and a prominent Radio Tower.