Arcadia, California, a city in Los Angeles County. It lies in the foothills of the San Gabriel Mountains, about 13 miles (21 km) northeast of downtown Los Angeles, of which it is a residential suburb. Santa Anita Race Track and Los Angeles State and County Arboretum are here. Arcadia was incorporated as a town in 1903 and chartered as a city in 1951. It has the council-manager form of government.