A view of the hills of southern Caithness. The Niveau Pliocene dominates the foreground. The chain of inselbergs represents the refashioned sub-Devonian surface.
Image by Alan Moar
Definition: Gently undulating land surfaces cut indiscriminately across underlying geology - the end-product of a long period of erosion.
Alain Godard (1965) recognises four cross-cutting erosion surfaces in Caithness:
These surfaces form the main relief elements in the county and remain recognisable despite variable amounts of glacial erosion. Each reflects millions of years of erosion and each has been uplifted and deformed since its formation.