Peveril Castle crowns a steep hill overlooking Castleton in the Peak District. This area was a center of medieval lead mining and William the Conqueror appointed William Peveril (supposedly his illegitimate son) as bailiff of the royal lands here. The ruined castle that bears his name was usually called the Castle of the Peak in medieval times. It existed by the time the Domesday survey and comprises a triangular enclosure sloping upwards to a sheer drop at the rear.
The very ruinous curtain is probably William Peveril's, since I displays herringbone masonry typical of early Norman work and stone was easy to come by here. It is of some interest as an early stone enclosure with neither keep nor gatehouse originally. It would seem that the north wall, guarding the easiest approach, came first, with the western wall (overlooking the ravine) following. Henry II inserted the present gate arch, facing the town. The precipitous southeastern side of the bailey was not walled until the thirteenth century and the curtain here has since disappeared. Two round towers stood along it, though why there should have been towers on the edge of the cliff but none elsewhere is difficult to explain.
When the third William Peveril forfeited his estates in 1155, the castle was taken over by Henry II. Expenditure of 184 pounds in 1176-77, is just enough to account for the square keep which now dominates the castle. The keep has come down to us in good condition, preserving its ashlar facing except on two of the outside walls. As keeps go its is a modest structure, just two stories high, though the walls rise higher to protect the vanished roof. The entrance was at first-floor level as usual but there is no evidence for a fore building. Clearly the main accommodation was always in the bailey and the foundations of two successive halls.