On May 10, 1869, at Promontory Summit, Utah, a boisterous crowd gathered to witness the completion of one of the greatest engineering feats of the 19th century: the building of the transcontinental railroad. The electrifying moment- the realization of a dream first pursued by a farsighted and determined engineer decades earlier- marked the culmination of six years of grueling work. Peopled by the ingenious entrepreneurs whose unscrupulous financing got the line laid, the brilliant engineers who charted the railroad's course and hurdled the geological obstacles in its way, the armies of workers who labored relentlessly on the enterprise, and the Native Americans whose lives were destroyed in its wake, The Transcontinental Railroad is a remarkable story of greed, innovation and gritty determination. It reveals both why the railroad was built and how it would shape the nation, while shedding light on the politics and culture of mid-nineteenth century America. Produced by Mark Zwonitzer.