The American River (Spanish: Río de los Americanos) is a 120-mile-long river in California that runs from the Sierra Nevada mountain range to its confluence with the Sacramento River in the Sacramento Valley. Via the Sacramento River, it is part of the San Francisco Bay watershed. This river is fed by the melting snowpack of the Sierra Nevada and its many headwaters and tributaries, including the North Fork American River, the Middle Fork American River, and the South Fork American River. The American river is known for the discovery of gold at Coloma in 1848 that started the California Gold ... Source: Wikipedia