San Francisco, officially the City and County of San Francisco, is the financial, cultural, and transportation center of the San Francisco Bay Area, a region of more than 7.4 million people which includes San Jose and Oakland. The only consolidated city-county in California, it encompasses a land area of about 46.9 square miles (121 km) on the northern end of the San Francisco Peninsula, giving it a density of about 17,179 people per square mile (6,632/km).

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