San Francisco is in California. San Francisco, also translated as "San Francisco" and "San Francisco", is a port city on the Pacific coast of California, USA. It is a world-famous tourist attraction and the fourth most populous city in California. San Francisco is close to Silicon Valley, a world-famous science and technology industrial zone. It is one of the important technology research and development bases in the world, an important financial center on the west coast of the United States and the birthplace of the United Nations (Charter of the United Nations, 1945).

San Francisco has a Mediterranean climate. It is the San Francisco Bay Area, which is composed of cities along the San Francisco Bay. Famous scenic spots include the Golden Gate Bridge and Fisherman's Wharf. The climate is warm in winter and cool in summer with plenty of sunshine. It is close to many American national parks (such as Yosemite National Park) and Napa Valley, a wine-producing region in California. It is usually considered as "the most popular city for Americans". The San Francisco Bay Area is one of the world's important scientific, educational and cultural centers, with world-renowned institutions of higher learning, including the public University of California at Berkeley and the private Stanford University, and the world's top medical center, the University of California at San Francisco.