The Icknield Way connects important archaeological areas of Wessex and East Anglia. Its route is marked by numerous field monuments and ancient sites, both visible and invisible. These are often on a ridge overlooking the route, since the Way seldom follows the highest ground as its users wished to avoid the clay that often capped the chalk ridge. From an archaeological point of view, the Icknield Way is best described as a belt, studded with archaeological features placed irregularly along its length.
In many ways a walk along the Icknield Way Path gives us the opportunity to sample a whole range of ornithological habitats at whatever time of year, and it can be very surprising to discover just how bird communities vary along its length. Not that the Icknield Way is really a cross section of average lowland bird life, rather it follows a narrow divide between different habitats, just as it followed a natural line in the early landscape for man.
The rock underlying our walking route is almost exclusively chalk but the effect of this on plant life is often masked by the predominant glacial or postglacial deposits which overlie the chalk ridge. Soils result which, although seldom acid, vary in consistency from the heavy Boulder Clay of Essex and South Cambridgeshire, to the poor, light Breckland sand of Suffolk and Norfolk.
Throughout its length the Icknield Way runs over chalk, avoiding both the Chalk Marl and Gault Clay to the north and the Clay with Flints and glacial Boulder Clay, 25 metres thick and more, which caps the crest of the chalk to the south. The footpath strays onto the Boulder Clay where it loops a mile or two south near Chrishall and again near Brinkley. The Way runs mainly over open country where soils are light in texture, developed on the chalk itself or on overlying sandy deposits a few to several metres thick. East of Kentford, towards Thetford, extensive sands and gravels, mainly of glacial origin, mask the chalk and give the characteristic Breckland landscape.