The History of Pole Vaulting [wikipedia]

"Poles were used as a practical means of passing over natural obstacles in places such as the marshy provinces of Friesland in The Netherlands, along the North Sea, and the great level of the Fens of Cambridgeshire, Huntingdonshire, Lincolnshire and Norfolk. The artificial draining of these marshes created a network of open drains or canals intersecting each other. In order to cross these without getting wet, while avoiding tedious roundabout journeys over bridges, a stack of jumping poles was kept at every house and used for vaulting over the canals. "
- Pole Vaulting on Wikipedia