Probably the most beautiful city in America lies on a peninsula bordered on the West by the Pacific and in the North by the Golden Gate Strait and in the East by the San Francisco Bay. Two famous bridges span the bay: the world-famous Golden Gate Bridge and the Oakland Bay Bridge. The city is built over 40 hills, so that almost every street has wonderful views of the bay. One of San Francisco's main attractions is the 130-year-old cable cars, which are still a popular means of transport even today. Other sights include the Fisherman's Wharf with its restaurants and views of the bay; the former high security prison of Alcatraz, which lies on an island before the city and is open to visitors; Chinatown, the largest Asian settlement outside Asia; the pagoda-topped Japan Centre; as well as Ocean Beach and North Beach. The main shopping area is located around Union Square in the town centre.