Brown's Folly is a 39.9 hectare

Hectare

The hectare is a metric unit of area defined as 10,000 square metres , and primarily used in the measurement of land. In 1795, when the metric system was introduced, the are was defined as being 100 square metres and the hectare was thus 100 ares or 1/100 km2...

 biological and geological Site of Special Scientific Interest (SSSI) near the village of Bathford

Bathford

Bathford is a village and civil parish east of Bath, England. The parish, which includes Warleigh has a population of 1,753, and extends over .-History:...

 in Bath and North East Somerset

Bath and North East Somerset

Bath and North East Somerset is a unitary authority that was created on 1 April 1996 following the abolition of the County of Avon. It is part of the Ceremonial county of Somerset...

, notified in 1974. Also known as Farleigh (or Farly) Down Stone Quarry, it is operated as a nature reserve

Nature reserve

A nature reserve is a protected area of importance for wildlife, flora, fauna or features of geological or other special interest, which is reserved and managed for conservation and to provide special opportunities for study or research...

 by the Avon Wildlife Trust

Avon Wildlife Trust

The Avon Wildlife Trust aims to protect and promote wildlife in the area of the former county of Avon — now Bath and North East Somerset, Bristol, North Somerset and South Gloucestershire, in England...

 (AWT).

Brown's Folly is situated on steep west-facing slopes which overlook the River Avon

River Avon, Bristol

The River Avon is an English river in the south west of the country. To distinguish it from a number of other River Avons in Britain, this river is often also known as the Lower Avon or Bristol Avon...

. The calcareous soils

Calcareous

Calcareous is an adjective meaning mostly or partly composed of calcium carbonate, in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines.-In zoology:...

 have developed on Lower Lias

Lias Group

The Lias Group or Lias is a lithostratigraphic unit found in a large area of western Europe, including the British Isles, the North Sea, the low countries and the north of Germany...

 clays, fuller's earth

Fuller's earth

Fuller's earth is any non-plastic clay or claylike earthy material used to decolorize, filter, and purify animal, mineral, and vegetable oils and greases.-Occurrence and composition:...

 and oolitic limestone

Oolite

Oolite is a sedimentary rock formed from ooids, spherical grains composed of concentric layers. The name derives from the Hellenic word òoion for egg. Strictly, oolites consist of ooids of diameter 0.25–2 mm; rocks composed of ooids larger than 2 mm are called pisolites...

 strata of Jurassic age. The local geology is of major importance
in the context of the British Bathonian

Bathonian

In the geologic timescale the Bathonian is an age or stage of the Middle Jurassic. It lasted from approximately 167.7 Ma to around 164.7 Ma...

 stratigraphy

Stratigraphy

Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....

.

The site includes the remains of quarries used for the extraction of Bath Stone

Bath Stone

Bath Stone is an Oolitic Limestone comprising granular fragments of calcium carbonate. Originally obtained from the Combe Down and Bathampton Down Mines under Combe Down, Somerset, England, its warm, honey colouring gives the World Heritage City of Bath, England its distinctive appearance...

. These provide a rich variety of wildlife habitats. Downland flora has covered the spoilheaps where wild thyme

Wild thyme

Thymus serpyllum, known by the common names of Breckland Thyme, Wild Thyme or Creeping Thyme is a species of thyme native to most of Europe and North Africa. It is a low, usually prostrate subshrub growing to 2 cm tall with creeping stems up to 10 cm long, with oval evergreen leaves...

, harebell

Harebell

Campanula rotundifolia is a rhizomatous perennial flowering plant in the bellflower family native to temperate regions of the Northern Hemisphere.In Scotland, it is often known as the Bluebell...

 and nine species of orchid (including the rare Fly Orchid

Fly Orchid

Ophrys insectifera, the Fly Orchid, is a species of orchid and the type species of the genus Ophrys. It is native to Europe and favors sites with alkaline soil. The name arises because it resembles a fly, being totally dependent on flies and bees for pollination...

) are found. Yellow Bird's-nest

Monotropa hypopitys

Monotropa hypopitys, also known as Dutchman's Pipe, Yellow Bird's-nest or Pinesap, is a herbaceous perennial plant, formerly classified in the families Monotropaceae or Pyrolaceae, but now included within the subfamily Monotropoidiae of the blueberry family...

 occurs here. The damp cliff faces support a variety of fern

Fern

A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...

s, fungi and spiders. Pockets of ancient woodland on the lower slopes are home to woodpeckers, and unusual plants such as Bath asparagus

Ornithogalum pyrenaicum

Ornithogalum pyrenaicum, also called Prussian asparagus, wild asparagus, Bath Asparagus, Pyrenees star of Bethlehem or spiked star of Bethlehem, is a plant whose young flower shoots may be eaten as a vegetable, similar to asparagus.The common name "Bath Asparagus" comes from the fact it was once...

.

The old quarries

The old underground quarries are used for roosting by the Greater Horseshoe Bat

Greater Horseshoe Bat

The Greater Horseshoe Bat is a European bat of the Rhinolophus genus. Its distribution covers Europe, Africa, South Asia and Australia. It is the largest of the European Horseshoe Bats and is thus easily distinguished from other species...

, and five other bat species are present at the site. The main bat roost area is clearly marked on the survey created by the SMCC, and everyone is asked to avoid the area. Boris, the oldest Greater Horseshoe Bat ever recorded in Britain, was discovered at Brown's Folly in January 2000. The underground workings themselves are of great speleological and historical interest. They are extremely well decorated and contain many delicate stalactites and examples of gull formation (caves features formed by land slippage). The quarry workings provided stone for the façade of Buckingham palace.

Access

In 2000 access was unilaterally withdrawn by the Avon Wildlife Trust pending the results of a mine inspectors report on the safety of the mines. This report was required because of the health and safety at work act which affects employees/volunteers of Avon Wildlife Trust who might have to enter the mine to count the bats. These legal requirements do not affect leisure access by cavers. Prior to 2000 access to the mine was controlled by the Council of Southern Caving Clubs and cavers had coexisted with a thriving bat population with voluntary restrictions on the access during the bat roosting season. There is no evidence of caving activity adversely affecting the bat population. Other locations such as Box Freestone quarry have seen rising bat populations despite becoming very popular.

The tower

The site is named after a tower located within which was built by Colonel Wade Brown so as to provide employment during an agricultural recession. It was built in 1848 and has been designated as a Grade II listed building.

Conservation

Despite the AWT the old quarry is maintained by cavers and mine explorers who remove graffiti and litter as well as repairing damage and naturally-occurring falls to keep passages open and relatively safe.