Between 1840 and 1860, construction shifted to the west of the Appalachian mountain.
Due to the mountainous terrain of the Appalachians, the railroads in the region was used to facilitate business, industry, and migration of people.
The railroad system is one development that helped to shape the area into what it is today.
The many resources that were abundant in the West made the need for the rail system in the area to spread.
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