Since the Gold Rush, San Francisco's Chinatown has been a destination for sojourners, immigrants, locals, and tourists. Despite laws restricting Chinese immigration, Chinatown has thrived as a residential and commercial center. Designed for tourists and bearing little resemblance to real Chinese cityscapes, the streets and buildings have nonetheless been extensively documented in picture postcards, as have the residents, particularly from the 1890s to 1930s, the "Golden Age of Postcards." The cards, relatively few of which survive, were kept as visual souvenirs and mementos, or were mailed to family and friends.