Rail technology, combined with the use of telegraph communications, revolutionized US commerce in the nineteenth century, after the Civil War. Affordable steel was a major breakthrough in rail technology in that the steel tracks lasted longer than wooden ones. They could also support greater weights and withstand stress better, thus making railroad bridges safer. Larger trains were more efficient, as one could use one locomotive to pull more rail cars than in the past. This meant that larger shipments could be made efficiently, thus making railroad magnates millions of dollars. Stronger trains could also dependably climb steeper grades, thus giving the railroads greater access to more of the country; however, in some cases railroad workers still had to create tunnels since even the strongest locomotive was no match for some of the mountains of the Sierra Nevada.

Greater efficiency and safety in rail travel opened up the West for US economic exploitation. Large shipments of cattle could be made to the East, where beef brought a better price than it did in the West. The powerful locomotives could also pull refrigerated rail cars, thus giving Easterners access to produce grown on the West coast. Whereas in the past most major cities required access to navigable rivers or ocean ports, improvements in rail technology meant that a city could exist as part of a vital rail hub. Railroad improvements made it more efficient to ship larger cargoes from East to West.