San Francisco is in America.
California ( [ kælᵻˈfɔːrnjə , _ - ni.ə ] , ) is the most populous state in the United States and the third most extensive by area . California is a state located in the Western United States . Northern California , often abbreviated NorCal , is the northern portion of the U.S. state of California . San Francisco . With a density of about 18,581 people per square mile ( 7,174 people per km2 ) , San Francisco is the most densely settled large city ( population greater than 200,000 ) in California and the second-most densely populated major city in the United States after New York City .