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View series: The United States: a territorial history

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The Transcontinental Railroad

This map is part of a series of 20 animated maps showing the history of The United States: a territorial history.

The idea of creating a transcontinental rail link evolved at the same time as the concept of Manifest Destiny.


After much controversy over where the railroad would pass, the Pacific Railroad Act, adopted in 1862, granted contracts for the first line between Omaha and Sacramento to two companies: the Union Pacific Company for the eastern section from Nebraska and the Central Pacific Company for the western section from California.


Union Pacific hired large numbers of Army veterans, Irish immigrants, and Mormons from Utah worked on the railroad, which advanced rapidly across the Great Plains, despite Indian hostility to the ‘Iron Horse’.

The Central Pacific Company hired mostly Chinese labourers. The extremely severe weather conditions in the Sierra Nevada and the use of explosives to blast out tunnels led to high loss of life among the workers.


The two companies joined up at Promontory Point in Utah on May 10, 1869. Immediately, the telegraph stations sent the simple message “DONE” across the entire country.        

It had required six years of construction to lay the 2,826 kilometres of railroad, but now travellers could cross the country from East to West in a week, instead of the six months needed previously.

Soon the railroad was extended to San Francisco.


Several other transcontinental lines were laid down in the 1880s:


In the south, the Southern Pacific linked the Gulf of Mexico to Los Angeles.

This railroad was later extended to run from Kansas to California via Santa Fe.


In the north, the Northern Pacific linked Saint Paul to Portland and Seattle……. and was later doubled in length by the Great Northern Pacific which ran along the Canadian border.


In order to encourage greater investment in the railroads, new legislation allowed railroad companies to have access to public lands.

New lines sprung up wherever strips of lands, in some States 50 miles wide, could be cut up into squares. As owners of half of these land parcels, the companies could finance their railroads by selling these lots to individual farmers and thus they encouraged more settlements and greater development in the West.