Following the gold discovery in 1848, numerous mining camps sprang up along the American River. One of these was Negro Bar, first mined by African Americans in 1849. In 1855 the town of Granite City was laid out on that site by Army Captain Joseph Libbey Folsom. Having arrived in California in 1847 for the Mexican-American War, Folsom had purchased the 35,000-acre Mexican land grant Rancho Rio de los Americanos from the heirs of San Francisco merchant William Leidesdorff. The new town prospered, first as a busy staging center and later as a railroad depot. Folsom’s fondest wish came true in February 1856, when the first railroad in California officially opened: 22 miles of track connecting Granite City with Sacramento. However, he didn’t live to see it, and after his death in July 1855, the town was renamed in his honor. Folsom Prison opened in 1880, built to relieve over-crowding at San Quentin. Folsom Powerhouse—one of the first hydroelectric power houses in the United States—made history with the first long-distance transmission of electricity to Sacramento, 22 miles distant, in 1895. The Folsom Dam opened in 1956, providing much-needed relief from regional flooding, and creating Folsom Lake, a reservoir on the American River that is widely used for recreation. Several homes are historic 19th century houses, now privately occupied. Old Town Folsom offers unique shopping, restaurants, and the Folsom History Museum housed in an 1850s Wells Fargo Assay Office.