Old Harry Rocks are three

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. Ch ...

formations, including a

stack Stack may refer to: Places * Stack Island, an island game reserve in Bass Strait, south-eastern Australia, in Tasmania’s Hunter Island Group * Blue Stack Mountains, in Co. Donegal, Ireland People * Stack (surname) (including a list of people ...

and a stump, located at Handfast Point, on the

Isle of Purbeck The Isle of Purbeck is a peninsula in Dorset, England. It is bordered by water on three sides: the English Channel to the south and east, where steep cliffs fall to the sea; and by the marshy lands of the River Frome, Dorset, River Frome and Poo ...

Dorset Dorset ( ; Archaism, archaically: Dorsetshire , ) is a Ceremonial counties of England, ceremonial county in South West England. It is bordered by Somerset to the north-west, Wiltshire to the north and the north-east, Hampshire to the east, t ...

, southern

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

. They mark the most eastern point of the

Jurassic Coast The Jurassic Coast, also known as the Dorset and East Devon Coast, is a World Heritage Site on the English Channel coast of southern England. It stretches from Exmouth in East Devon to Studland Bay in Dorset, a distance of about , and was ins ...

, a UNESCO

World Heritage Site World Heritage Sites are landmarks and areas with legal protection under an treaty, international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural ...

Location

Old Harry Rocks lie directly east of Studland, about north east of

Swanage Swanage () is a coastal town and civil parish in the south east of Dorset, England. It is at the eastern end of the Isle of Purbeck and one of its two towns, approximately south of Poole and east of Dorchester, Dorset, Dorchester. In the Unit ...

, and about south of the large towns of

Poole Poole () is a coastal town and seaport on the south coast of England in the Bournemouth, Christchurch and Poole unitary authority area in Dorset, England. The town is east of Dorchester, Dorset, Dorchester and adjoins Bournemouth to the east ...

and

Bournemouth Bournemouth ( ) is a coastal resort town in the Bournemouth, Christchurch and Poole unitary authority area, in the ceremonial county of Dorset, England. At the 2021 census, the built-up area had a population of 196,455, making it the largest ...

. To the south are the chalk cliffs of Ballard Down, much of which is owned by the

National Trust The National Trust () is a heritage and nature conservation charity and membership organisation in England, Wales and Northern Ireland. The Trust was founded in 1895 by Octavia Hill, Sir Robert Hunter and Hardwicke Rawnsley to "promote the ...

. The rocks can be viewed from the Dorset section of the

South West Coast Path The South West Coast Path is England's longest waymarked Long-distance footpaths in the UK, long-distance footpath and a National Trail. It stretches for , running from Minehead in Somerset, along the coasts of Devon and Cornwall, to Poole Harb ...

Formation

The chalk of Old Harry Rocks used to be part of a long stretch of chalk between Purbeck and the Isle of Wight, but remained as a headland after large parts of this seam were eroded away. As the headland suffered hydraulic action (a process in which air and water are forced into small cracks by the force of the sea, resulting in enlarging cracks), first caves, then arches formed. The tops of the arches collapsed after being weakened by rainfall and wind, leaving disconnected stacks. One of these stacks is known as Old Harry. Old Harry's Wife was another stack which was eroded through corrosion and abrasion, until the bottom was so weak the top fell away, leaving a stump. Hydraulic action is the main cause of erosion ( shear force of the waves) that damaged the rock and caused it to fall away.

Geology

The

downland Downland, chalkland, chalk downs or just downs are areas of open chalk hills, such as the North Downs. This term is used to describe the characteristic landscape in southern England where chalk is exposed at the surface. The name "downs" is deriv ...

s of Ballard Down are part of the Portsdown Chalk Formation, containing some bands of

flint Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start ...

, and were formed 84–72 million years ago in the

Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...

age of the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the more recent of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''cre ...

. The bands of stone have been gradually

eroded 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 disti ...

over the centuries, some of the earlier stacks having fallen (Old Harry's original wife fell in 1509), while new ones have been formed by the breaching of narrow isthmuses. Across the water to the east,

The Needles The Needles are a row of three stacks of chalk that rise about out of the sea off the western extremity of the Isle of Wight in the English Channel, United Kingdom, close to Alum Bay and Scratchell's Bay, and part of Totland, the weste ...

on the Isle of Wight are usually visible. These are also part of the same chalk band and only a few thousand years ago were connected to Ballard Down. To form the stacks, the sea gradually eroded along the joints and bedding planes where the softer chalk meets harder bedrock of the rock formations to create a cave. This eventually eroded right through to create an arch. The arch subsequently collapsed to leave the stacks of Old Harry and his wife, No Man's Land (the large outcrop of rock at the end of the cliffs) and the gap of St Lucas' Leap. Old Harry is formed by erosion processes, which will eventually remove the stack, whilst new stacks develop. Some people desire to preserve the rocks and protect them from the erosive processes that formed Old Harry. The

, who own the stacks in perpetuity, have experience in looking after the coast, and have found that "working with natural processes is the most sustainable approach".

Legend

There are various stories about the naming of the rocks. One legend says that the

Devil A devil is the mythical personification of evil as it is conceived in various cultures and religious traditions. It is seen as the objectification of a hostile and destructive force. Jeffrey Burton Russell states that the different conce ...

(traditionally known euphemistically as "Old Harry") slept on the rocks. Another local legend says that the rocks were named after Harry Paye, the infamous Poole

pirate Piracy is an act of robbery or criminal violence by ship or boat-borne attackers upon another ship or a coastal area, typically with the goal of stealing cargo and valuable goods, or taking hostages. Those who conduct acts of piracy are call ...

, whose ship hid behind the rocks awaiting passing merchantmen. Yet another tale has it that a ninth-century Viking raid was thwarted by a storm and that one of the drowned, Earl Harold, was turned into a pillar of chalk.

References

Bibliography

External links

Geology of Harry Rocks and Ballard Point
Ian West, University of Southampton
Old Harry Rocks, Dorset: GCSE Geography
BBC Bitesize {{Jurassic Coast Isle of Purbeck Landforms of Dorset Stacks of England Geology of Dorset Tourist attractions in Dorset Jurassic Coast