The U. P. Trail takes place in the late 1860s during the building of the Union Pacific Railroad, the first to connect the east coast to the west. Our protagonist is Warren Neale, a civil engineer on the railroad. His girlfriend, Allie Lee, seems to be always in need of recusing. One of the most interesting characters is Neales best friend Larry "Red" King, a rough gun toting Texan cowboy. The heroes must battle the human challenges of greed, ruthlessness, and ambition, as well as the tremendous challenges of nature, to make the rail connection between East and West. The U. P. Trail is one of Zane Greys most detailed and panoramic Western novels; indeed, it is first-rate historical fiction in addition to being one of his most gripping romance-adventures.