Title: San Francisco
Content:  San Francisco (Spanish for "Saint Francis"), officially the City and County of San Francisco, is a cultural, commercial, and financial center in the U.S. state of California. Located in Northern California, San Francisco is the 17th most populous city in the United States, and the fourth most populous in California, with 873,965 residents as of 2020. It covers an area of about 46.9 sqmi, mostly at the north end of the San Francisco Peninsula in the San Francisco Bay Area, making it the second most densely populated large U.S. city, and the fifth most densely populated U.S. county, behind only four of the five New York City boroughs. San 
Title: San Francisco Peninsula
Content:   The San Francisco Peninsula is a peninsula in the San Francisco Bay Area that separates San Francisco Bay from the Pacific Ocean. On its northern tip is the City and County of San Francisco. Its southern base is in northern Santa Clara County, including the cities of Sunnyvale, Palo Alto, Mountain View, and Los Altos. Most of the Peninsula is occupied by San Mateo County, between San Francisco and Santa Clara counties, and including the cities and towns of Atherton, Belmont, Brisbane, Burlingame, Colma, Daly City, East Palo Alto, El Granada, Foster City, Hillsborough, Half Moon Bay, La Honda, Loma Mar, Los Altos, Menlo Park, Millbrae, Mountain View, Pacifica, Palo Alto, Pescadero, Portola Valley, Redwood City, San Bruno, San Carlos, San Mateo, South San Francisco, Sunnyvale, and Woodside. Whereas the term peninsula in a geographical sense technically refers to the entire San Francisco Peninsula, in local jargon, "The Peninsula" does not include the city of San Francisco.
Title: San Francisco
Content:  County of San Francisco. San Francisco's largest jail complex (County Jail No. 5) is located in San Mateo County, in an unincorporated area adjacent to San Bruno. San Francisco was also granted a perpetual leasehold over the Hetch Hetchy Valley and watershed in Yosemite National Park by the Raker Act in 1913. San Francisco serves as the regional hub for many arms of the federal bureaucracy, including the U.S. Court of Appeals, the Federal Reserve Bank, and the U.S. Mint. Until decommissioning in the early 1990s, the city had major military installations at the Presidio, Treasure Island, and Hunters Point—a legacy still 
Title: San Francisco County Superior Court
Content:  The Superior Court of California of the County of San Francisco is the state superior court with jurisdiction over the City and County of San Francisco.
Title: Sacramento County, California
Content:  Sacramento County is a county located in the U.S. state of California. As of the 2020 census, the population was 1,585,055. Its county seat is Sacramento, which has been the state capital of California since 1854. Sacramento County is the central county of the Greater Sacramento metropolitan area. The county covers about 994 sqmi in the northern portion of the Central Valley, on into Gold Country. Sacramento County extends from the low delta lands between the Sacramento River and San Joaquin River, including Suisun Bay, north to about ten miles (16 km) beyond the State Capitol and east into the foothills of the Sierra Nevada Mountains. The southernmost portion of Sacramento County has direct access to San Francisco Bay.
Title: Fresno County, California
Content:  Fresno County, officially the County of Fresno, is a county located in the central portion of the U.S. state of California. As of July 1, 2019, the population was 999,101. The county seat is Fresno, the fifth most populous city in California. Fresno County comprises the Fresno, CA Metropolitan Statistical Area, which is part of the Fresno-Madera, CA Combined Statistical Area. It is located in the Central Valley, south of Stockton and north of Bakersfield.
Title: San Mateo County, California
Content:  San Mateo County, officially the County of San Mateo, is a county located in the U.S. state of California. As of the 2010 census, the population was 718,451. Redwood City is the county seat, and the third most populated city following Daly City and San Mateo. San Mateo County is included in the San Francisco-Oakland-Berkeley, CA MSA (metropolitan statistical area), Silicon Valley, and is part of the San Francisco Bay Area, the nine counties bordering San Francisco Bay. It covers most of the San Francisco Peninsula. San Francisco International Airport is located in the northeastern area of the county and is approximately 7 miles south of the city and county limits of San Francisco. The county's built-up areas are mostly suburban, and are home to several corporate campuses.
Title: San Francisco
Content:  The 2020 United States census showed San Francisco's population to be 873,965, an increase of 8.5% from the 2010 census. With roughly one-quarter the population density of Manhattan, San Francisco is the second-most densely populated large American city, behind only New York City among cities greater than 200,000 population, and the fifth-most densely populated U.S. county, following only four of the five New York City boroughs. San Francisco forms part of the five-county San Francisco–Oakland–Hayward, CA Metropolitan Statistical Area, a region of 4.7 million people, and has served as its traditional demographic focal point. It is also part of the greater 14-county San Jose-San Francisco-Oakland, CA Combined Statistical Area, whose population is over 9.6 million, making it the fifth-largest in the United States as of 2018.
Title: Santa Clara County, California
Content:  Santa Clara County, officially the County of Santa Clara, is California's 6th most populous county, with a population of 1,936,259, as of the 2020 census. Santa Clara County and neighboring San Benito County together form the U.S. Census Bureau's San Jose-Sunnyvale-Santa Clara, CA Metropolitan Statistical Area, which is part of the larger San Jose-San Francisco-Oakland, CA Combined Statistical Area. Santa Clara is the most populous county in the San Francisco Bay Area and in Northern California. The county seat and largest city is San Jose, the 10th most populous city in the United States, California's 3rd most populous city and the most populous city in the San Francisco Bay Area. Home to Silicon Valley, Santa Clara County is an 
Title: California's 17th State Assembly district
Content:  The district encompasses the eastern portions of the consolidated city-county of San Francisco, including its central financial and governmental core as well as several of the more working-class neighborhoods of the city. San Francisco County – 58.1%

Question: what county is san francisco?
Answer: San Francisco.