His ambition was not simply to visit as many countries as possible or collect photographs from famous destinations. He wanted to establish an uninterrupted journey on foot, moving from one place to the next without using transport to advance along his route. When circumstances forced him to stop, he could pause, deal with the problem, and eventually return to the exact point where he had left off.
The distinction was crucial. A person might walk thousands of miles across several continents while flying between regions. Bushby wanted to preserve the continuity of the journey itself.
According to his expedition website, he established two central rules: he would not use transport to move himself forward along the route, and he would not return home until he had completed the challenge on foot.
These rules transformed an ambitious walking expedition into something much more demanding. Every geographical obstacle became a problem that had to be solved without compromising the central promise.
A river might require a bridge or a swim. A mountain range demanded a route through difficult terrain. A border could bring weeks or months of negotiations. A sea separating two continents could turn into a problem that ordinary travelers would solve with a ferry or airplane.