The City and County of San Francisco is the fourth most populous city in California and the 13th most populous city in the United States, with a 2008 estimated population of 808,976 The second most densely populated major city in the U.S it is the financial, cultural, and transportation center of the larger San Francisco Bay Area, a region of more than 7 million people The city is located at the northern end of the San Francisco Peninsula, with the Pacific Ocean to the west and San Francisco Bay to the north and east.