My local hill is artificial, about the same size as Silbury, but with a larger footprint and more shallow slope. The by-product of a motorway cutting experiment that went wrong - and sliced the city in two. A more interesting hill is called Proudy, in the south tyne valley, which is a drumlin. Very large. This is featured in very many alignments and, in full profile, strongly resembles an Egyptian pyramid. To me this suggests very widely spread trade routes, that were only supposed to have arrived with the Romans.