As the holiday rush moves into full throttle, the U.S. Postal Service is predicting that Monday will be the season's busiest mailing day for the packages and cards Americans use to send their loved ones season's greetings. It's estimated that 5.5 billion cards, letters, flats and packages will be sent through the mail this season and—even though use of the USPS web services is also expected to peak on Monday—that's sure to mean that many Americans will find themselves waiting in line to get their bundles weighed, stamped and sent.
But while the mail sent today will likely be delivered in familiar trucks or planes, the postal service has employed a number of delivery techniques over the years, from horse-drawn carriages to surprising snow plows. Here are just a few of those vehicles from more than 100 years of postal history, as seen in photographs from the collection of the National Postal Museum.