The City and County of San Francisco is the fourth-largest city in the U.S. state of California and the fourteenth largest in the United States.

San Francisco is famous for its hills. A "hill" in San Francisco is an elevation that is over 100 ft (30 m). There are a total of 42 hills within city limits. Some of these hills are neighborhoods such as Nob Hill, Pacific Heights, Russian Hill, and Telegraph Hill, while some of these hills are public parks and open space such as Twin Peaks, Mount Sutro, Mount Davidson, and Buena Vista Park.