- "I fooled you. I fooled you. I got pig iron. I got pig iron. I got all pig iron."
– Lonnie Donegan, "Rock Island Line"
Railroad allows construction of Machine Gun units and the Mining Inc wonder. Most importantly, with Coal or Oil it allows your Workers to upgrade your roads to railroads, vastly increasing your units' movement.
The predecessors to modern railroads were wagonways, which were constructed in England starting in the 16th century. Wagonways were roads of parallel planks upon which coal wagons were pulled by horses at a greater speed than would have been possible on dirt roads. Wagonways were gradually improved by adding cross-ties and iron strips to reinforce the track. Eventually, the planks became metal rails, and evolved into the type of rails used on today's railroads by the start of the 19th century. Soon after the steam locomotive was introduced in 1829, it replaced horse-drawn wagons, giving birth to the railroad. Originally developed in Britain and the eastern United States as a method of hauling heavy mining ores and freight, railroads outshone canals in their ability to operate across any ground and in nearly any weather. When railroads started carrying passengers as well as goods, the potential for safe, fast, inexpensive transport became clear. Railroads led to a dramatic increase in the amount of cargo, passengers, news, and troops that could be moved quickly over great distances.