I believe that the greatest innovation in history was the railroad. During the time it was built, the train enabled the population to cover much larger distances in a shorter amount of time. The train replaced the horse, which was more unreliable because a horse requires constant care and transported its rider a shorter distance in a longer time. The train also offers a more comfortable setting than a horse and requires less maintenance. Furthermore, the train enables more people to travel at the same time with less man power, which increases efficiency of travel for the rider. The invention of the train significantly reduced travel times and made the world a smaller place. The train was developed during the Industrial Revolution around the early 19th century. As the world around us was becoming more modern, a way of efficient travel was necessary for businessmen and women to communicate in a more productive manner.