Entitled: A cross roads shelling of ammunition trains. Sketch shows shells landing near an American convoy in France, including horse-drawn wagons, in World War I by Lucien Jonas. A convoy is a group of vehicles, typically motor vehicles or ships, traveling together for mutual support and protection. The ammunition train was an element of armies in 19th and 20th century warfare. They were responsible for transporting the artillery and infantry ammunition of each division from the ammunition refilling point to the area of engagement. Depending on the era, its conveyance would be horse-drawn wagons or motor vehicles, and it was assigned the necessary personnel and equipment to fulfill these roles.