The Purbeck Hills, also called the Purbeck Ridge or simply the Purbecks, are a ridge of

chalk Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Cha ...

downs in

Dorset Dorset ( ; archaically: Dorsetshire , ) is a county in South West England on the English Channel coast. The ceremonial county comprises the unitary authority areas of Bournemouth, Christchurch and Poole and Dorset. Covering an area of ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe ...

. It is formed by the structure known as the Purbeck Monocline. The ridge extends from

Lulworth Cove Lulworth Cove is a cove near the village of West Lulworth, on the Jurassic Coast in Dorset, southern England. The cove is one of the world's finest examples of such a landform, and is a World Heritage Site and tourist location with approximat ...

in the west to Old Harry Rocks in the east, where it meets the sea. The hills are part of a system of chalk downlands in southern England formed from the

Chalk Group The Chalk Group (often just called the Chalk) is the lithostratigraphic unit (a certain number of rock strata) which contains the Upper Cretaceous limestone succession in southern and eastern England. The same or similar rock sequences occur ac ...

which also includes

Salisbury Plain Salisbury Plain is a chalk plateau in the south western part of central southern England covering . It is part of a system of chalk downlands throughout eastern and southern England formed by the rocks of the Chalk Group and largely lies w ...

and the

South Downs The South Downs are a range of chalk hills that extends for about across the south-eastern coastal counties of England from the Itchen valley of Hampshire in the west to Beachy Head, in the Eastbourne Downland Estate, East Sussex, in the ea ...

. For most of their length the chalk of the Purbeck Hills is protected from

coast The coast, also known as the coastline or seashore, is defined as the area where land meets the ocean, or as a line that forms the boundary between the land and the coastline. The Earth has around of coastline. Coasts are important zones in n ...

erosion Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is di ...

by a band of resistant Portland limestone. Where this band ends, at Durlston Head, the

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay part ...

and chalk behind has been eroded, creating

Poole Poole () is a large coastal town and seaport in Dorset, on the south coast of England. The town is east of Dorchester and adjoins Bournemouth to the east. Since 1 April 2019, the local authority is Bournemouth, Christchurch and Poole Council ...

Bay and the

Solent The Solent ( ) is a strait between the Isle of Wight and Great Britain. It is about long and varies in width between , although the Hurst Spit which projects into the Solent narrows the sea crossing between Hurst Castle and Colwell Bay ...

. The ridge of steeply dipping chalk that forms the Purbeck Hills continues further east on the

Isle of Wight The Isle of Wight ( ) is a Counties of England, county in the English Channel, off the coast of Hampshire, from which it is separated by the Solent. It is the List of islands of England#Largest islands, largest and List of islands of England#Mo ...

. The height of the chalk ridge and proximity to

Poole Harbour Poole Harbour is a large natural harbour in Dorset, southern England, with the town of Poole on its shores. The harbour is a drowned valley ( ria) formed at the end of the last ice age and is the estuary of several rivers, the largest being th ...

and the south coast have made the hills of strategic importance. There are a number of

Iron Age The Iron Age is the final epoch of the three-age division of the prehistory and protohistory of humanity. It was preceded by the Stone Age (Paleolithic, Mesolithic, Neolithic) and the Bronze Age (Chalcolithic). The concept has been mostly appl ...

, Roman and

Saxon The Saxons ( la, Saxones, german: Sachsen, ang, Seaxan, osx, Sahson, nds, Sassen, nl, Saksen) were a group of Germanic * * * * peoples whose name was given in the early Middle Ages to a large country ( Old Saxony, la, Saxonia) near the No ...

archaeological Archaeology or archeology is the scientific study of human activity through the recovery and analysis of material culture. The archaeological record consists of artifacts, architecture, biofacts or ecofacts, sites, and cultural landscape ...

sites, such as

Nine Barrow Down Nine Barrow Down is an elongated hill forming the northern ridge of the Purbeck Hills on the Isle of Purbeck in Dorset, England. The chalk down is part of the extensive Southern England Chalk Formation. The eastern end of the ridge, which carr ...

. At

Corfe Castle Corfe Castle is a fortification standing above the village of the same name on the Isle of Purbeck peninsula in the English county of Dorset. Built by William the Conqueror, the castle dates to the 11th century and commands a gap in the ...

the hills are broken twice leaving a steep round hill between the ridges on which stood a

medieval In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire a ...

castle, guarding the only easy route through the hills, until the

English Civil War The English Civil War (1642–1651) was a series of civil wars and political machinations between Parliamentarians ("Roundheads") and Royalists led by Charles I ("Cavaliers"), mainly over the manner of Kingdom of England, England's governanc ...

of the 17th century, when it was

slighted Slighting is the deliberate damage of high-status buildings to reduce their value as military, administrative or social structures. This destruction of property sometimes extended to the contents of buildings and the surrounding landscape. It is ...

. Some of the ridge, around the village of Tyneham, near Lulworth, has been closed to the public for use by the

army An army (from Old French ''armee'', itself derived from the Latin verb ''armāre'', meaning "to arm", and related to the Latin noun ''arma'', meaning "arms" or "weapons"), ground force or land force is a fighting force that fights primarily on ...

as a firing range. This has protected them from damage from farming and development, and these areas are now nature reserves. At the eastern end Ballard Down is a

National Trust The National Trust, formally the National Trust for Places of Historic Interest or Natural Beauty, is a charity and membership organisation for heritage conservation in England, Wales and Northern Ireland. In Scotland, there is a separate and ...

nature reserve A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, or features of geological or ...

which is managed for its calcareous grassland

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

Named hills

(199 m) * Ridgeway Hill (199 m) * Creech Barrow Hill (193 m) - sometimes counted as part of the Dorset Heaths * Bindon Hill (168 m), overlooking

References

External links

''The Purbeck Hills''
at dorsetlife.co.uk. {{coord, 50, 38, N, 2, 07, W, display=title, region:GB_type:mountain_source:GNS-enwiki Hills of Dorset Isle of Purbeck

Named hills

See also

References

External links