Beeston Castle (Cheshire)
This is one of the largest castles in England (by acreage); perched on a hill with a high crag; very impressive, but few buildings remain; why it was built so massively is rather problematical, since even though it dominates the area between North Wales and the Peak District, it is not very strategic in location -- probably a very ambitious and devious local land baron was up to something unsavory. This would have made a great refuge for a gang of bandits (like Carreg Cennan in Wales). Across the valley you can see the towers of a privately-owned Victorian castle (Peckforton), a monumental effort of a different sort. Beeston is a great castle to take a dog to. The castle is in Cheshire, near the M6 motorway, but is rather hard to find.