Birks Fell Caves

Site of Special Scientific Interest · 54.1837, -2.1012

Condition (Natural England)

Favourable (1)
UnitFeatureConditionArea (ha)Assessed
SD934764 Favourable 85.93 2015-01-19

Geology & landscape

Geological Feature: Cave / Cavern, Karst · Geological Period: Quaternary · Rock Type: Limestone

Landscape processes: Glacial, Karst

Description

Area, 85.5 hectares 211.2 ac. Description Birks Fell Caves comprise two independent underground systems which, although different interms of scale, show a remarkable similarity of form and development which is unseen elsewhere in Northern England. Formed during the Ice Age, in the later Pleistocene period, these linear systems lie almost parallel to the glacial trough of Upper Wharfedale. These passages however follow lines which bear little relationship to present day surface form but rather exploit structural weaknesses such as bedding planes, joints and faults, in the limestone in which they have developed. The caves are outstanding hydrologically in the way in which they demonstrate this complete independence of channels, a characteristic feature of karst, or limestone, drainage. As a result of continued surface water percolation into these systems many fine cave formations, including some of the best twisted stalactites or helictites in Britain, are found here.