It is believed that millions of dollars of gold, depending on current value, still lays buried deep in the earth below the quaint town of Grass Valley. Prospectors from Oregon in search of gold and emigrants from the east looking for a place to call home settled in Grass Valley between 1848 and 1849. As with all the mining camps and towns along what would eventually become Highway 49, gold fever created an instantaneous population explosion. Though early miners expected to find their riches in the streams, it was only by accident that the true wealth of Grass Valley was discovered.
There were two major mines within miles of Grass Valley: The Empire Mine and the North Star Mine. 150 million dollars was mined from the two combined. Nevada County, the county Grass Valley is in, made a combined 440 million dollars in that same time period.