San Francisco Bay Area contains many international airports.
 After the United States joined World War II in 1941, the Bay Area became a major domestic military and naval hub, with large shipyards constructed in Sausalito and across the East Bay to build ships for the war effort
The Bay Area cities of Vallejo, Suisun City, Oakland, San Leandro, Fairfield, and Richmond are among the most ethnically diverse cities in the United States

