Humans are animals and like all animals we leave tracks as we walk: signs of passage made in snow, sand, mud, grass, dew, earth or moss…. We easily forget that we are track-markers, though, because most of our journeys now occur on asphalt and concrete–and these are substances not easily impressed.
Touch is a reciprocal action, a gesture of exchange with the world. To make an impression is also to receive one, and the soles of our feet, shaped by the surfaces they press upon, are landscapes themselves with their own worn channels and roving lines.
Robert Macfarlane, The Old Ways: A Journey on Foot