Sutter received 2,000 fruit trees in 1847, which started the agriculture industry in the Sacramento Valley. In 1848, when gold was discovered by James W. Marshall at Sutter's Mill in Coloma (located some 50 miles (80.5 km), northeast of the fort), a large number of gold-seekers came to the area, increasing the population.
John Sutter, Jr. then planned the City of Sacramento 2 miles south of New Helvetia, in association with Sam Brannan against the wishes of his father, naming the city after the Sacramento River for commercial reasons. He hired topographical engineer William H. Warner to draft the official layout of the city, which included 26 lettered and 31 numbered streets (today's grid from C St. to Broadway and from Front St. to Alhambra Blvd.). However, a bitterness grew between the elder Sutter and his son as Sacramento became an overnight commercial success (Sutter's Fort, Mill and the town of Sutterville, all founded by John Sutter, Sr., would eventually fail).