San Francisco, formerly known as "San Francisco" or "San Francisco," is a port city on the Pacific coast of California, USA. It is a world-renowned tourist destination and the fourth largest city in California's population. San Francisco is located near the world-renowned technology industry district of Silicon Valley, and is one of the world's important technology research and development bases and an important financial center on the West Coast of the United States. It is also the birthplace of the United Nations (Charter of the United Nations in 1945).

San Francisco has a Mediterranean climate, forming the San Francisco Bay Area with various cities along the San Francisco Bay. Famous attractions include the Golden Gate Bridge and Fisherman's Wharf. The climate is warm in winter and cool in summer, with ample sunshine. It is adjacent to many American national parks (such as Yosemite National Park) and the California wine producing Napa Valley, and is often praised as the "most popular city among Americans".  In 1769, the Spanish discovered this place and joined the United States in 1848. In the mid-19th century, it rapidly developed during the gold rush, and overseas Chinese referred to it as "Golden Mountain". Later, it was renamed "San Francisco" to distinguish it from Melbourne (New Golden Mountain) in Australia. As of July 2018, the population of San Francisco was approximately 880000, of which 180000 were of Chinese descent. It is one of the regions with the highest density of Chinese in the Western Hemisphere, and the total number of Chinese is second only to New York.