Fairy Holes Cave is a Site of Special Scientific Interest

Site of Special Scientific Interest

A Site of Special Scientific Interest is a conservation designation denoting a protected area in the United Kingdom. SSSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in Great Britain are based upon...

 in the Wear Valley

Wear Valley

Wear Valley was, from 1974 to 2009, a local government district in County Durham, England. Its council was based in Crook.The district covered much of the Weardale area. In the west it was parished and rural, whereas in the east it was more urban...

 district of west County Durham

County Durham

County Durham is a ceremonial county and unitary district in north east England. The county town is Durham. The largest settlement in the ceremonial county is the town of Darlington...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

. It is located on the western flanks of Snowhope Moor, on the right bank of Westernhope Burn, some 3 km south-west of the village of Eastgate

Eastgate, County Durham

Eastgate is a village in County Durham, England. It is situated in Weardale, a few miles west of Stanhope.Eastgate originally marked the eastern border of the private hunting park of the Prince Bishops of Durham. This was second in extent only to the royal hunting park of the New Forest in Hampshire...

.

The cave is the longest known stream passage in the Yoredale Limestone

Limestone

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....

 of the North Pennines

North Pennines

The North Pennines is the northernmost section of the Pennine range of hills which runs north-south through northern England. It lies between Carlisle to the west and Darlington to the east...

 and the best developed example of its type. The Geological Conservation Review

Geological Conservation Review

The Geological Conservation Review is produced by the UK's Joint Nature Conservation Committee and is designed to identify those sites of national and international importance needed to show all the key scientific elements of the geological and geomorphological features of Britain...

classes it as being of national importance.