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25-614: The Folkestone Downs are an area of chalk downland above Folkestone , where the eastern end of the North Downs escarpment meets the English Channel . Part of the Downs is the Folkestone to Etchinghill Escarpment Site of Special Scientific Interest , designated for its geological and biological interest. Folkestone Downs stretch for 5 kilometres from East Cliff and Warren Country Park in

50-604: A 20% loss in that period and an assessment of chalk grassland in Dorset found that over 50% had been lost between the mid-1950s and the early 1990s. Much remaining chalk downland has been protected against future development to preserve its unique biodiversity . Berkshire Downs The Berkshire Downs are a range of chalk downland hills in southern England , part of the North Wessex Downs Area of Outstanding Natural Beauty . The Berkshire Downs are wholly within

75-440: A chalk rendzina soil consists of only a shallow dark humus rich surface layer which grades through a lighter brown hillwash containing small pellets of chalk, to the white of the chalk itself. This is largely because of the purity of the chalk, which is about 98% calcium carbonate , and the consequent absence of soil-building clay minerals which are abundant, for example, in valley floors. Steep slopes on chalk downland develop

100-567: A much gentler dip slope on the other. Where the downs meet the sea, characteristic white chalk cliffs form, such as the White Cliffs of Dover and Beachy Head . Chalk deposits are generally very permeable, so the height of the water table in chalk hills rises in winter and falls in summer. This leads to characteristic chalk downland features such as dry valleys or coombes , and seasonally-flowing streams or winterbournes . The practice of extracting water from this aquifer, in order to satisfy

125-426: A ribbed pattern of grass covered horizontal steps a foot or two high. Although subsequently emphasised by cattle and sheep walking along them, these terracettes (commonly known as sheep tracks) were formed by the movement of soil downhill, a process known as soil creep . The dominant habitat in chalk downland is typically calcareous grassland , formed by grazing from both livestock and wild animals. Chalk downland

150-568: Is a major business in the area, with much of the downs covered with training areas, and stables centred on the village of Lambourn . The Berkshire Downs can be accessed from various cities via the Great Western Main Line and its current single operator runs localised stopping trains as well as the high-speed trains along the Vale of White Horse calling at major stops Swindon and Didcot Parkway . From Reading to Newbury trains run along

175-712: Is formed by Salisbury Plain , mainly in Wiltshire . To the southwest, downlands continue via Cranborne Chase into Dorset as the Dorset Downs and southwards through Hampshire as the Hampshire Downs onto the Isle of Wight . To the northeast, downlands continue along the Berkshire Downs and Chiltern Hills through parts of Berkshire , Oxfordshire , Buckinghamshire , Hertfordshire , Bedfordshire and into Cambridgeshire . To

200-487: Is often unsuitable for intensive agriculture , horticulture , or development because of the nutrient-poor, shallow soil and difficult slopes. For this reason downland often survived uncultivated when other, more easily worked land was ploughed or reseeded. This shallow soil structure makes downland ecosystems extremely fragile and easy to destroy. With modern machinery and fertilising techniques, it has become possible to use some previously uncultivated downland for farming, and

225-509: Is one of the largest areas of unimproved chalk downland in Kent. The extensive flora includes many typical species found in chalk grassland including horseshoe vetch ( Hippocrepis comosa ), squinancywort ( Asperula cynanchica ) and small scabious , as well as scarce species such as bedstraw broomrape ( Orobanche caryophyllacea ). Many species of orchid grow on the downs notably the nationally rare late spider orchid ( Ophrys fuciflora ), as well as

250-500: Is relatively soft porous white chalk with only poorly-defined bedding. The chalk is classified as a biomicrite , with microscopic coccoliths and other fine-grained fossil debris in a matrix of micrite mud. Small amounts of silica were also deposited, mainly from sponge spicules , which moved during diagenesis and accumulated to form flints . The Chalk Group either directly overlies the impermeable uppermost Lower Cretaceous Gault Clay or permeable Upper Greensand Formation above

275-938: The Marlborough Downs to the west and the Chilterns to the east. In the east they are divided from the Chilterns by Goring Gap on the River Thames . In the west their boundary is generally taken to be the border between Berkshire and Wiltshire , although the downs in Wiltshire between the Berkshire border and the valley of the River Og are sometimes considered to be part of the Berkshire Downs. English downland has attracted human habitation since prehistoric times. The ancient track known as

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300-637: The Gault Clay. Since its deposition, the chalk in southern England has been uplifted, faulted , fractured and folded by the distant effects of the Alpine Orogeny . The fracturing has greatly increased the chalk's permeability, such that it is a major aquifer . Sedimentary basins formed by rifting during the Triassic to Early Cretaceous were inverted during the Late Paleogene to Miocene leading to

325-545: The Ridgeway runs along the Berkshire Downs. Prehistoric sites in the Downs include Wayland's Smithy ( Neolithic ), numerous tumuli (Neolithic or Bronze Age ), Uffington White Horse (Bronze Age), Liddington Castle and Uffington Castle (Bronze Age and Iron Age ), and Segsbury Camp and Grim's Ditch (Iron Age). It is generally thought that in Anglo-Saxon times the downs were known as Æscesdūn or Ashdown, and that it

350-468: The chalk and the modification of existing valleys due to a combination of frozen ground and snowmelt . Downland develops when chalk rock becomes exposed at the surface. The chalk slowly erodes to form characteristic rolling hills and valleys. As the Cretaceous chalk layer in southern England is typically tilted, chalk downland hills often have a marked scarp slope on one side, which is very steep, and

375-491: The decline of extensive grazing has meant that many areas of downland, neither cultivated nor grazed, revert to scrub or other less rare habitat, essentially destroying the delicate calcareous grassland. The UK cover of lowland calcareous grassland has suffered a sharp decline in extent since the middle of the twentieth century. There are no comprehensive figures, but a sample of chalk sites in England surveyed in 1966 and 1980 showed

400-522: The downs including the Adonis blue ( Lysandra bellargus ), chalkhill blue ( Polyommatus coridon ) and small blue ( Cupido minimus ). Several rare species of moth have been recorded including the straw belle ( Aspitates gilvaria ) and the annulet moth ( Charissa obscurata ). Much of Folkestone Downs is owned by Eurotunnel and managed by the White Cliffs Countryside Project . Grazing

425-689: The east downlands are found north of the Weald in Surrey , Kent and part of Greater London , forming the North Downs . To the southeast the downlands continue into West Sussex and East Sussex as the South Downs . Similar chalk hills are also found further north in Lincolnshire and Yorkshire where they are known as the Wolds . The Chalk Group is a sequence of Upper Cretaceous limestones . The dominant lithology

450-624: The east to Peene Quarry in the west. The downs rise steeply above the town of Folkestone to heights in excess of 150 metres. The highest point is Dover Hill at 170 metres. The Channel Tunnel Terminal lies at the foot of the downs and the British portal is directly below the slopes of Castle Hill. The downland is classified as CG4 Brachypodium pinnatum and CG5 Bromus erectus - Brachypodium pinnatum calcareous grassland with smaller areas of CG2 Festuca ovina - Avenula pratensis grassland. There are also areas of scrubland and woodland. Folkestone Downs

475-591: The formation of structures such as the Wealden Anticline and the Portland-Wight Monocline . Later erosion has produced the characteristic ridges of the downland landscape. The landscape was further modified during the Quaternary period by the area's proximity to the southern edge of the ice sheets formed during the last ice age . These periglacial effects included significant amounts of dissolution of

500-423: The increasing demand for water, may be putting some of these streams under stress. In the valleys below the downs at the base of the chalk layer, greensand or gault clay comes to the surface and at the interface at the top of the gault a springline can occur where water emerges from the porous chalk or the underlying greensand. Along this line, settlements and farms were often built, as on the higher land no water

525-463: The nationally scarce early spider orchid ( Ophrys sphegodes ) and man orchid ( Aceras anthropophorum ). The nationally scarce burnt orchid ( Neotinea ustulata ) has also been recorded in the past. Folkestone Downs is also notable for its extensive lichen flora. The scrub and woodland provide breeding habitats for many species of birds. Folkestone Downs is particularly notable for its insect fauna. Up to 32 species of butterfly have been recorded on

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550-519: The traditional county of Berkshire , although split between the current ceremonial counties of Berkshire and Oxfordshire . The western parts of the downs are also known as the Lambourn Downs . The Berkshire Downs run east–west, with their scarp slope facing north into the Vale of White Horse and their dip slope bounded by the course of the River Kennet . Geologically they are continuous with

575-663: Was abandoned after the Second World War resulting in an invasion of coarse grasses and scrub. This resulted in a reduction of the grassland flora, particularly after the rabbit population was reduced by myxamatosis in the 1950s. Cattle grazing was resumed in 1990. Much of the downland is designated as open access land following the Countryside and Rights of Way Act 2000 . 51°6′N 1°9′E  /  51.100°N 1.150°E  / 51.100; 1.150 Chalk downland The largest area of downland in southern England

600-557: Was available. This is demonstrated very clearly beneath the scarp of the White Horse Hills , above the Vale of White Horse . In many chalk downland areas there is no surface water at all other than artificially created dewponds . The soil profile of chalk downland in England is a thin soil overlaying the parent chalk . Weathering of the chalk has created a characteristic soil known as rendzina . Unlike many soils in which there are easily distinguished layers or soil horizons ,

625-622: Was here that the Battle of Ashdown was fought in 871. In 1915, after a brief stint as a hospital orderly at the British hospital for French soldiers in Haute-Marne , John Masefield moved to his country retreat at Lollingdon Farm . The setting at the foot of the Downs - Masefield's "Lollingdon Downs" would inspire a number of poems and sonnets. Downland pasture is firm and well drained, suited to grazing sheep and grazing and training horses. Horse racing

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