The Chinatown centered on Grant Avenue and Stockton Street in San Francisco, California, is the oldest Chinatown in North America and the largest Chinese enclave outside Asia. It is also the oldest and largest of the four notable Chinese enclaves within San Francisco. Since its establishment in 1848, it has been highly important and influential in the history and culture of ethnic Chinese immigrants in North America. Chinatown is an enclave that continues to retain its own customs, languages, places of worship, social clubs, and identity. There are two hospitals, several parks and squares, numerous churches, a post office, and other infrastructure. Recent immigrants, many of whom are elderly, opt to live in Chinatown because of the availability of affordable housing and their familiarity with the culture. San Francisco's Chinatown is also renowned as a major tourist attraction, drawing more visitors annually than the Golden Gate Bridge.