The Pony Express was a fast mail

Mail

Mail, or post, is a system for transporting letters and other tangible objects: written documents, typically enclosed in envelopes, and also small packages are delivered to destinations around the world. Anything sent through the postal system is called mail or post.In principle, a postal service...

 service crossing the Great Plains

Great Plains

The Great Plains are a broad expanse of flat land, much of it covered in prairie, steppe and grassland, which lies west of the Mississippi River and east of the Rocky Mountains in the United States and Canada. This area covers parts of the U.S...

, the Rocky Mountains

Rocky Mountains

The Rocky Mountains are a major mountain range in western North America. The Rocky Mountains stretch more than from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States...

, and the High Sierra

High Sierra

High Sierra is an early heist film and film noir written by W.R. Burnett and John Huston from the novel by Burnett. The movie features Ida Lupino and Humphrey Bogart and was directed by Raoul Walsh on location at Whitney Portal, halfway up Mount Whitney.The screenplay was co-written by Bogart's...

 from St. Joseph, Missouri, to Sacramento, California

Sacramento, California

Sacramento is the capital city of the U.S. state of California and the county seat of Sacramento County. It is located at the confluence of the Sacramento River and the American River in the northern portion of California's expansive Central Valley. With a population of 466,488 at the 2010 census,...

, from April 3, 1860 to October 1861. It became the west's most direct means of east-west communication before the telegraph

First Transcontinental Telegraph

The First Transcontinental Telegraph was a milestone in electrical engineering and in the formation of the United States of America. It served as the only method of near-instantaneous communication between the east and west coasts during the 1860s....

 and was vital for tying California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 closely with the Union

Union (American Civil War)

During the American Civil War, the Union was a name used to refer to the federal government of the United States, which was supported by the twenty free states and five border slave states. It was opposed by 11 southern slave states that had declared a secession to join together to form the...

 just before the American Civil War

American Civil War

The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

.

The Pony Express was a mail delivery system of the Leavenworth & Pike's Peak Express Company of 1849 which in 1850 became the Central Overland California and Pikes Peak Express Company

Central Overland California and Pikes Peak Express Company

The Central Overland California and Pike's Peak Express Company was the parent company of the Pony Express.It was formed by William Russell, Alexander Majors and William Waddell, as a freighting company supplying goods to the western United States...

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