Few periods of Samuel Clemens’ life are as empty of detail as the time he spent in San Francisco. He lived there two years with mixed success as a local reporter. He would never set a story in the city, never return later in life, and never say the famous line: “The coldest winter I ever spent was summer in San Francisco.”

But one important thing did happen here: Clemens walked onto a stage for the first time. The topic of his “lecture” was Hawaii, or the Sandwich Islands, where he had spent nearly half a year. For that first lecture—or stand-up comedy show—he was very nervous, so he made up a poster with these words along the bottom: “Doors open at 7 1/2, the trouble will begin at 8.” It was the beginning of a lifelong success for the performer known as Mark Twain.