High Rocks

Site of Special Scientific Interest · 51.1229, 0.2276

Condition (Natural England)

Favourable (2)
UnitFeatureConditionArea (ha)Assessed
TQ559382 Favourable 1.97 2023-02-06
TQ560383 Favourable 1.36 2023-02-06

Geology & landscape

Geological Period: Quaternary · Rock Type: Sandstone

Landscape processes: Periglacial

Description

Area, 3.2 ha. 7.9 ac. Description High Rocks is a key geomorphological site for sandstone weathering features developed on the highest cliffs in the Weald. The Ardingly Sandstone is gently cambered deformed and the joints have opened out to form spectacular gulls tension cracks which are wide enough in places for a person to enter. Open gulls are comparatively rare in Britain, except in the central Weald and they are nowhere better displayed than in the great extent of open passages at High Rocks. The Ardingly Sandstone is friable and poorly cemented, but the surface develops a protective crust and displays a variety of micro weathering features, notably honeycombing and polygonal cracking. The origin of this cracking is problematic but may relate to freezing and thawing under periglacial conditions during the Pleistocene. It is found in Britain only on the sandstone outcrops in the central Weald and is nowhere better displayed than at High Rocks.