The National Postal Museum’s collection of international artifacts representing postal transportation is relatively small, but the objects it does hold fall into two main themes: vehicles and signaling devices.
Vehicles form the backbone of the postal network because they allow large volumes of mail to be transported over great distances. Stagecoaches were some of the first vehicles used to transport the mail, but as technology evolved, they gave way to railroads, trucks, and airplanes.
Another type of transportation artifact that may not be as obvious as the vehicles is a signaling device. The post horn was originally a musical instrument used to warn of danger or attack during wartime, but it soon became the sound of the postman. For over four centuries post riders announced their arrival, departure, and distress by playing one of eight different signals on their horns.
Allison Marsh, National Postal Museum