The American River Canyon below Auburn is seen as a natural and scenic area but still contains signs of an extensive historical past. This includes historic bridges and bridge sites dating back to the 1850s. The 1849 Gold Rush brought 75 years of mining that ended after massive dredges worked the river for its gold in the 1910s. Unique to the canyon is the Mountain Quarries Railroad, which traveled its way across 17 trestles and an elegant, still-standing concrete bridge to reach the main line in Auburn. The long-stalled Auburn Dam is the latest incarnation of earlier dams, like the 1890s Birdsall Dam that diverted water for 50 years through the North Fork Ditch to communities downstream.