The discovery of gold fields has long attracted large numbers of prospectors and other people because of the traditionally high value of gold. Towns developed overnight, transportation networks were hacked out of the wilderness, and new territories were born within months.
Gold rushes in the United States.
The greatest gold rush in United States history began with the discovery of gold by James Marshall at Sutter's Mill in California on Jan. 24, 1848. By 1849, a large-scale gold rush was underway. San Francisco, the nearest port, grew from a small town to a city of 25,000 in a year's time as people arrived from all over the world. By 1850, California had enough people to be admitted to the Union as a state. Gold rush prospectors California set the pattern for other gold rushes throughout the West.