Ross (formerly, Sunnyside) is a small incorporated town in Marin County, California, United States, just north of San Francisco. Ross is located 1.5 miles (2.4 km) west-southwest of San Rafael, at an elevation of 36 feet (11 m). The population was 2,415 at the 2010 census. The town is bordered by Kentfield and Greenbrae to the east, Larkspur to the south and San Anselmo to the north.
According to the United States Census Bureau, the town has a total area of 1.6 square miles (4.0 km²), all of it land.
In 1857, James Ross (1812–1862) bought Rancho Punta de Quentin. Ross, a Scot who had arrived in San Francisco from Australia in 1848 and made his fortune in the wholesale liquor business, set up a trading post called "Ross Landing".