San Francisco's Chinatown, around Grant Avenue, is often touted as the "oldest" and "largest" East Asian district in the U.S. The original Chinese residents in San Francisco gravitated to this area to work for, or do business with, other Chinese people. General discrimination and even official "exclusion" laws made it difficult for 19th and early 20th century immigrants to do anything besides work as laborers on railroads or in mines.
San Francisco drew different Cantonese-speaking groups. Waves of immigrants came from what is now Guangdong province and from Hong Kong. In the 1970s, Cantonese-speaking refugees from Vietnam's Chinatowns chose this area to settle as well. Though many of the descendants of the original Chinatown residents have left San Francisco and moved to the suburbs, they return during festival times such as the Lunar New Year.