At the southern extremity of the White Peak lies the seldom visited area which, topographically, drains to the Bradbourne Brook. It is dominated by reef limestones, with distinctive dolomites to the west which can be seen as the periglacial weathered tors of Rainster and Harborough Rocks. To the south lies the small isolated Kniveton - Bradbourne limestone inlier.
Of geological interest is the Tertiary Brassington Formation, preserved as silica sand pockets up to 43m thick in large solution collapse hollows scattered over a 4km wide area from Parsley Hay to Brassington.
Along the limestone margin small sinks lie to the west of Parwich, but their risings are unknown. Small springs feed the Bletch and Havenhill Dale Brooks, as at Parwich, Ballidon, and Brassington, but some drainage from the area may go westwards to rise in the Dove. Also of interest are the dry valleys and gorges at Hipley Dale and Ballidon.
It seems unlikely that large penetrable caves exist, but digging at the sinks, coupled with a dye testing programme, may yield interesting results.