In 1900, Calhoun left Euclid Heights and moved to San Francisco, California. He merged the street railways of that city into a single firm, the United Railroads of San Francisco (URR), and became the company president in 1906. He then gave local political boss Abe Ruef $200,000 ($ in dollars) to allow him to build overhead electric wires to supply his streetcars with power. Calhoun was indicted and placed on trial several times, but eventually charges against him were dismissed when his political supporters won office.