OR76BOOM03 Rail Gun WW1 Boche BusterA Railway gun (or railroad gun) is a large artillery piece, often surplus naval artillery, mounted on, transported by, and fired from a specially designed railway wagon. Many countries have built railway guns, but the best known are the large Krupp built pieces used by Germany in World War I and World War II. Smaller guns were often part of an armoured train. Only able to be moved where there were good tracks, which could be destroyed by artillery