A saddlebag is a pouch or bag designed to hang on either side of a saddle, whether on a horse, bicycle, or motorcycle. Originally, saddlebags were essential equipment for horseback riders who needed to carry supplies on long journeys. Cowboys might pack food or tools in their saddlebags, while a traveling doctor in the Old West would carry medical supplies.

The design is simple but clever: the bag drapes over the saddle with one pouch hanging down each side, keeping the weight balanced. This matters because uneven weight makes riding uncomfortable and can even injure the horse.

Today, cyclists use saddlebags to carry spare tubes, snacks, or school supplies without wearing a backpack. Motorcycle riders attach larger saddlebags for road trips, following the same basic principle their great-great-grandparents used when traveling by horse.