"Stories, like paths, relate in two senses: they recount and they connect. In Siberia, the Khanty word usually translated as 'story' also means 'way'. A disputed etymology suggests that our word 'book' derives from the High German bok, meaning 'beech' - the tree on whose smooth bark marks and signs were often incised in order to indicate routes and paths. Our verb 'to write' at one point in history referred specifically to track-making: the Old English writan specifically meant 'to incise runic letters in stone'; thus one would 'write' a line by drawing a sharp point over and into a surface - by harrowing a track.
As the pen rises from the page between words, so the walker's feet rise and fall between paces, and as the deer continues to run as it bounds from the earth, and the dolphin continues to swim even as it leaps again and again from the sea, so writing and wayfaring are continuous activities, a running stitch, a persistence of the same seam or stream."
ETA: Robert Macfarlane will be appearing at a Festival of Walking, Writing and Ideas at Aberdeen University on 28th/29th. August.