ABSTRACT
For as far as we know, humanity has been a mobile species. In order to survive, our ancestors had to learn to move as the seasons changed to follow their source of food or to avoid clashing with neighbouring tribes. As more severe changes occurred – ice ages, severe draughts, foreign invasions – they had to fi nd new places to settle by covering great distances. At the beginning of human history, travel must have been a dreaded necessity, dangerous and unpleasant – a last resort in life-threatening circumstances.
