Sources: Railroads and the Making of Modern America, University of Nebraska, Lincoln (Rail Network). US Census Bureau (Urban Population).
In only 30 years after its introduction, the American rail network totaled about 28,900 miles (46,500 km) on the eve of the Civil War (1861-1865). Yet the American rail network consisted of two systems that reflected the political division between the North (Union States) and the South (Confederate States). Outside a connection through Washington, the networks were disconnected and served different economic systems. This lack of connectivity was compounded by the fact that railways serving the same city were often not connected, requiring cargo to be ferried from one terminal to the other and passengers to spend a night to catch the next-day train (schedules were not effectively coordinated).
The predominantly rural society of the South was served mainly by penetration lines that connected the agricultural hinterland to ports where surpluses were exported (e.g., New Orleans & Charleston). As such, the network was not very cohesive. The more urbanized North developed a network that interconnected its main urban centers and agricultural regions in the Midwest in a complex lattice. At the end of the Civil War, the expansion of the network and its level of integration would resume.