Architectural historian Gail Cornell talks about the history of the Tweed Courthouse, including the exploits of William M. "Boss" Tweed and Tammany Hall. The Old New York County Courthouse, better known as Tweed Courthouse, is the legacy of Tammany Hall boss William M. Tweed, who controlled the initial construction. Built over a period of twenty years, between 1861 and 1881, it is the product of two of New York’s most prominent nineteenth-century architects, John Kellum and Leopold Eidlitz. Grandly scaled and richly decorated, the courthouse retains its original spatial arrangement, including thirty monumental courtrooms and a five-story central rotunda.