I think it was because transportation was made way easier and it offered better options for people who wanted to travel. Also i believe at the time the west was rich because of the foreseen treasures such as gold found there so people wanted to travel west to get rich.
Ok well all of them affected migration because each of them were able to expand outward from the thirteen colonies. This is because each was usually for trading, but eventually turned into people being able to travel. <span>The National Road, or Cumberland Road, was the first highway built by the federal government. </span><span>Though canals offered tremendous advantages over land shipment, they could not compete with the efficiency and flexibility of the railroad. </span><span>With improved methods of transportation came the concept of Manifest Destiny.
Your main 3 transportation routes are:
National Railroad Baltimore and Ohio Railroad Erie Canal
Evidence #1 first example/ piece of evidence that's supports your claim evidence#2 ^ same as number 1 evidence#3^same as #1 and then the summary/ conclusion sentences in a sentence or two restate your claim / argument
