|British World War I military cyclist recruitment poster|
Although motorized vehicles were available during World War I (1914-1918), they were not as numerous or as reliable as today. This would have been the era of the Ford Model T. Both bicycles and horses were used by the military. Horses were used primarily for moving supplies in western Europe. Cyclists were used for a variety of purposes. Some bikes were adapted to hold rifles, so soldiers could cover greater distances than they could by marching. Others were used as ambulances to transport the wounded. Vickers manufactured a tandem tricycle that carried two machine guns. Unfortunately it weighed nearly 400 pounds without the riders, so it wasn't all that mobile.
Communication was often difficult in World War I. The telegraph was well developed, but radio was relatively new. Marconi won a share of the Nobel Prize for Physics for his work developing radio just five years before the war started. Carrier pigeons were even used to communicate during the war. Cyclists were often used as messengers, which was a pretty dangerous job. The most famous of these cyclist messengers, or "radfahrer" as the Germans called them, was a corporal from Austria named Adolph Hitler.