A transcontinental railroad in the United States' is any continuous rail line connecting a location on the U.S. Pacific coast with one or more of the railroads of the nation's eastern trunk line rail systems operating between the Missouri and/or Mississippi Rivers and the U.S Atlantic coast. The first concrete plan for a transcontinental railroad in the United States was presented to Congress by Asa Whitney in 1845.
The world's First Transcontinental Railroad was built between 1863 and 1869 to join the eastern and western halves of the United States. Begun just preceding the American Civil War, its construction was considered to be one of the greatest American technological feats of the 19th century. Known as the "Pacific Railroad" when it opened, this served as a vital link for trade, commerce, and travel and opened up vast regions of the North American heartland for settlement. Shipping and commerce could thrive away from navigable watercourses for the first time since the beginning of the nation. Much of this line is currently used by the California Zephyr, although some parts were rerouted or abandoned.
The coming of the railroad resulted in the end of most of the far slower and more hazardous stagecoach lines and wagon trains, and it led to a great decline of traffic on the Oregon and California Trail, which had helped populate much of the West. The transcontinental railroad provided much faster, safer, and cheaper transportation (one week from Omaha to San Francisco via emigrant sleeping car at a fare of about $65 for an adult) for people and goods across the western two-thirds of the continent.