January 24, 1848, was a big day for James W. Marshall, who found gold at Sutter's Mill (about 45 miles northeast of Sacramento). Word of his discovery quickly spread around the world, kicking off the California Gold Rush. Over the next seven years, hundreds of thousands of people flocked to what would become the 31st U.S. state.
The population influx changed California dramatically. Small settlements turned into boomtowns, steamship arrived, and railroads were built.
But the growth came with ugly consequences. Native Americans were forcibly removed from their settlements as prospectors closed in. An estimated 4,500 died in violent altercations with miners or of the new diseases they brought with them. Discrimination lingered within the mining camps as whites chased off and assaulted Chinese, Mexican, and Chilean newcomers. The newly formed State Legislature even levied a $20 (over $500 today) monthly licensing fee to work in the gold fields in 1850 (they dropped the tax to $3 (a little over $80 today) the following year). Meanwhile, the mining process itself led to environmental damage as arsenic and mercury leaked into streams and soil.
The chance of a lone miner finding gold on his own became nearly impossible by 1855. By then, the gold extraction process had turned corporate. Meanwhile, newly irrigated land and the completion of the First Transcontinental Railroad helped give the fast-growing state a more diverse range of economic opportunities.
But in those initial days of the Gold Rush, maps of California were created with prospectors in mind, labeling where the gold and quartz mines could be found. Below, courtesy the Library of Congress, a look at some of those maps:
"Topographical sketch of the gold & quicksilver district of California" (1848)
One of the earliest maps from the Gold Rush, this provides an informative but tough-to-read explanation of where the gold is. Descriptions of what is being found are placed according to location:
"Map of the gold regions of California" (1849)
This British map, made by the geographer to the Queen and Prince Albert, is less descriptive, with the gold-exploring zones highlighted in ... gold:
"Map of the mining district of California" (1850)
Made two years into the Gold Rush, this map provides simple markings that indicate not only where the gold is, but where the Native Americans can be found:
"Map of the mining district of California" (1851)
A similarly structured map, this one identifies where gold exploration is occurring and the where quartz veins are: