The united states spread across the continent, the transport system helped a lot in the growth of this great nation. it all started in the late 1700 and early 1800 to improve the movement of people and goods.
The network of Roads, Steamboats, canals, and Railroad was developed which provided fast transportation and growth.
The railroads open the new road of settlement in the west which provided new economic opportunities in remote areas also increased the growth rate of towns and cities and tied the country together through its huge network.