Insider trading, bribery, graft and all sorts of dirty money are behind the major players on Nob Hill. On this two-hour guided walking tour, see how The Big 4 (the Railroad Barons) and The Little 4 (the Silver Kings) spent their ill-gotten booty, and visit San Francisco's beautiful Union Square, America's favorite shopping district. You'll also see distinctive snobby architecture: mansions, hotels and churches while learning interesting details about the Great Earthquake and Fire of 1906 and the invention of the cable car. The tour covers 12 city blocks in about two hours.