The document discusses the Transcontinental Railroad that was built in the United States in the 1860s. It summarizes that the Pacific Railway Act of 1862 established the construction of the railroad by the Union Pacific and Central Pacific railroads to link Omaha, Nebraska to Sacramento, California. Thousands of Irish, Union and Confederate veterans, and Chinese immigrant laborers worked to build the tracks. On May 10, 1869 the two railroads met at Promontory Summit, Utah where the final "Golden Spike" was driven, connecting the first transcontinental railroad and revolutionizing travel across North America.