* Maybe wheeled suitcases wouldn’t have been very useful until the last hundred years or so, as people would have been wheeling their suitcases through the mud or across bumpy cobblestones. Since at least the 1870s, however, wheeled suitcases would have been very handy at the great train stations of the world, such as those in New York, London, and Berlin. By this accounting, it still took at least one hundred years for someone to come up with this simple innovation.