San Francisco, California, the fourth most populous city in the state. It occupies all of San Francisco County. The city lies on the tip of the San Francisco Peninsula, overlooking the Pacific Ocean on the west, San Francisco Bay on the east, and the Golden Gate (the entrance to the bay) on the north. With a magnificent natural setting and architecturally distinctive buildings, San Francisco is generally regarded as one of the nation's most beautiful cities. It is also a hub of commerce, a cultural and educational center, and a city of diverse nationalities.