Geograph - photograph every grid square

A view over the parapet (the unavoidable little buff triangle in the bottom right-hand corner) from Nottingham Castle, with the junction of Hope and Peveril Drives in The Park below. At school fifty years ago we were told it was Bunter Sandstone; now it's been reclassified as Lenton Sandstone. Whatever it's called, it's soft, in places pebbly, and easily tunnelled. Mortimer's Hole is below, and the sandstone hills of the old parts of the city are full of ancient cellars, store rooms and passages.