It's a good place for gold, said people in the 1840s, and they came from all over the world. It's a good place for a prison, said the US government in the 1920s, and they put Al Capone there on the island of Alcatraz. It's a good place for love, said the hippies in the 1960s, and they put flowers in their hair and came to Haight Ashbury. And San Francisco is still a good place — to take a hundred photographs, or see the Chinatown parade, or just to sit in a coffee shop and be in this interesting, different city...