30 - Southern Magnesian Limestone : Description

Physical and functional links to other National Character Areas

The Southern Magnesian Limestone is a very long, narrow National Character Area (NCA) stretching from Nottinghamshire in the south through north Derbyshire to North Yorkshire in the north. The limestone ridge runs roughly north to south and this elevation provides visual links to and from the lower-lying land to both the west and the east.

Several major rivers cut through the ridge – the Ure, Nidd and Wharfe flow east from the Pennine Dales Fringe NCA, while the Aire and Don flow in from the west from the Nottinghamshire, Derbyshire and Yorkshire Coalfield NCA, all eventually joining the Humber to the east. The naturally desired routes of the Rother and the Erewash are both blocked by the ridge, meaning that they run further north and south respectively before finding their way through. These river corridors provide important ecological connectivity, as well as communications routes and, in the past, locations for key defensive structures. Water draining from the Coal Measures influences the plant communities of semi-natural habitats along the west and south edges.

In the past there have been significant economic links between the fertile farmland on the ridge and the industrial areas to the west.

The Southern Magnesian Limestone today

The underlying Permian Magnesian Limestone forms a distinct but low ridge of land running north to south, cut through by rivers following some dramatic gorges. Towards the north the limestone is largely covered by drift deposits, so that the ridge is less obvious, but the whole area is unified by the widespread use of the local limestone as a building material. The well-drained soils and low altitude have given rise to a landscape of rolling landform, fertile farmland and well-wooded estates. The ridge forms an escarpment with a steep scarp face to the west and a gentle slope dipping to the east, elevated enough to give long views out over the more industrialised lowlands to the west and the farmed lowlands to the east.

The soils are free draining and very fertile, giving rise to productive arable cropping. The fields are generally large and geometric, bounded by low, flailed hawthorn hedges, although stone walls do also occur, for example as estate boundaries and in villages. Hedgerow trees are infrequent, which adds to the open character of the farmed landscape, and the hedges often emphasise the rolling landform. This open, rolling farmland contrasts with the scattered woodlands and supports important populations of farmland birds including lapwing, grey partridge, yellow wagtail, tree sparrow and corn bunting.

Woodland cover is reasonably high overall, often owing to the trees and woodlands in the grounds of the many large country houses that were established on the ridge plateau. Historical evidence suggests that woodland cover is currently higher than at the time of the Domesday Book records. Many are plantation woodlands, but oak, ash and lime typically form the canopy of deciduous woodlands. The few remnants of ancient woodland in this area have a particular abundance of the nationally scarce large-leaved lime. A good example is Sprotbrough Gorge where the canopy consists of ash and wych elm and is the largest area of this woodland type in South Yorkshire. Where hazel forms the understory, woodland can be particularly important for dormouse, and this NCA has been identified as a priority area for its conservation. The woodlands support a wide range of birds including lesser spotted woodpecker, marsh tit, spotted flycatcher and hawfinch.

The designed parklands and gardens, supported by estates, are a major influence on the landscape. With their extensive areas of woodlands, plantations and game coverts, in places they give the feel of a well-wooded landscape. The estates include early monastic abbeys such as Fountains Abbey and Newstead Abbey, and later; country houses established with the wealth generated from the industrialisation of the coalfield to the west. Designed parklands include the internationally renowned gardens at Studley Royal, along with Newby Hall, Bramham Park, Lotherton Hall, Brodsworth Park, Hardwick Hall and Annesley Hall. Fountains Abbey is part of the Studley Royal and Fountains Abbey World Heritage Site and provides outstanding value to the area through the designed landscape and associated Cistercian abbey.

Other semi-natural habitats are limited and fragmented. Of particular note are the small areas of Magnesian Limestone (calcareous) grassland, which is characteristic of this landscape. It is a nationally scarce habitat, and has a number of rare specialist species such as Yorkshire broomrape and the brown argus butterfly which is associated with it. These grasslands tend to occur on steeper slopes or in the narrow valley bottoms, and some of the most significant stretches can be found around Maltby, west of Sprotbrough, and near Castleford, Micklefield and Bramham. Where they are not actively managed, they are replaced by scrub, which forms a particularly varied mix, with hawthorn, blackthorn, guelder rose and dogwood, providing important habitat for birds and insects.

The river valleys that cut through the limestone ridge are picturesque, with some dramatic gorges with overhanging woodlands. These include Nidd Gorge at Knaresborough, the Don Gorge near Conisbrough and Creswell Crags. In medieval times defensive castles were built on the high land of gorges such as these, giving them control over movements up and down the river valleys, and these castles – such as Knaresborough, Conisbrough, Mexborough and Tickhill – still remain as striking features in the landscape.

The rivers continue to play an important role in connecting the industrial towns to the west with the Humber and the North Sea to the east. Historically the rivers were important transport corridors. Along some valleys, such as the Aire, there are widespread industrial influences including evidence of mining spoil, power lines, railways, roads, subsidence depressions and ings where sand and gravel have been extracted. Areas in the south around Nottingham aremore heavily settled where the limestone is more faulted, giving rise to more industrial activity as a result of the availability of coal and other materials.

Most of the settlements have more in common with the traditional former mining towns and villages lying to the west and grew up to service the large industrial towns. Only a few are rural limestone villages, with red pantile roofs. Limestone buildings can be found in towns such as Wetherby, Tadcaster, Boston Spa and Ripon, in the villages and isolated large farmsteads, and in estate boundary walls, as well as in the defensive castles such as at Conisbrough. These contrast with the later factories and terraces of workers’ housing in urban areas which were built in brick with slate roofs.

The importance of the limestone as a building material is reflected in the presence of a number of large limestone quarries, for example near Bolsover, while the quality of the water abstracted from the limestone aquifers has contributed to the development of breweries (for example at Masham and Tadcaster) and spas (Boston Spa). In the north, associated with the valleys of the Ure and Swale, deposits of sand and gravel have also been exploited, and wetlands created from the altered landforms.

The limestone ridge has played an important role in connecting communities from prehistory, with a series of henges and other features running down the ridge from Thornborough to Ferrybridge. There is evidence of Roman camps and settlements linked by the main north-south route which followed the drier, elevated land, and which now forms the A1. The M1, M18 and M62 all cross the ridge, linking west with east. These major roads introduce traffic noise, and are often highly visible along their length. This accessibility by road and rail to routes running both north-south and east-west has given rise to a large number of warehousing sites over recent years. Access for people is less well established within the NCA with low levels of access routes. Formal access is provided by the established parks and gardens of the large estates such as the gardens at Newby Hall. The extent of parkland has reduced over recent decades, but as Registered Parks and Gardens cover 2.5 per cent of the area, they remain a key influence on the character of the landscape, as well as being home to many veteran trees, important for the insects and lichens that they support. Many of the parklands are now open to the public, providing important access opportunities.

The landscape through time

Underlying the NCA are the Upper Carboniferous Coal Measures, a sequence of river-lain sandstones, silts and muds and, at depth, coal. Exposed in the deeper river valleys, it has had a significant influence on the modern development of the NCA as a source of mined coal and the local use of sandstone in buildings. The NCA is dominated by the easterly dipping Permian Magnesian Limestone escarpment. The Magnesian Limestone was deposited on the western edge of a shallow tropical sea (similar to the Bahamas) approximately 250-260 million years ago and forms a continuous belt from Nottingham to the Durham coast. It comprises a lower unit of dolostone and dolomitic limestones (the Cadeby Formation), which forms the dominant landscape feature, overlain by red mudstone with gypsum (the Edlington Formation). Following on from this is the upper dolostone and dolomitic limestone unit (the Brotherton Formation) followed by more red mudstone and gypsum (the Roxby Formation). The sequence locally has a number of swallow holes caused by the underground dissolution of gypsum and limestone. The Magnesian Limestone sequence is clearly seen where it is cut by rivers, for example in the Nidd Gorge at Knaresborough, the Wharfe Valley at Wetherby, Boston Spa and the Don Gorge near Doncaster.

Exposures in the Magnesian Limestone, often associated with former quarries, provide important and accessible sections allowing interpretation and understanding of and continued research into the geodiversity of the NCA. The best examples of these exposures are protected as Sites of Special Scientific Interest, for example at Quarry Moor near Ripon and Cadeby Quarry.

North of Wetherby the Magnesian Limestone is largely covered with glacial deposits from the last glaciations. South of Wetherby the Magnesian Limestone has only a thin local cover of glacial deposits. The soils here are derived from the limestones and, locally, their associated red clays. They are generally very fertile and often support agricultural land classified as Grade 2 in quality. Internationally important evidence of early use of this landscape by humans is found in the caves at Creswell Crags. Creswell Crags provides evidence of three phases of occupation. The earliest, 40,000-60,000 years ago, corresponds to a Neanderthal occupation of migrating hunter gatherers and is evidenced through stone tools; there is also evidence of occupation approximately 32,000-33,000 years ago by modern hunter gatherers and lastly upper Palaeolithic hunters 14,000–15,000 years ago. Tools and animal remains found in the caves provide important evidence of the adaptation of humans to the late glacial and early post-glacial environments and the caves also contain the only evidence of Palaeolithic art in the country. The area was extensively exploited by hunter-gatherer groups during the Mesolithic Period and the succeeding Neolithic Period saw the construction of several important groupings of barrows and henge monuments, particularly around Thornborough Henges between the Ure and the Swale rivers. The intact quality of the three henges at Thornborough and their position in a landscape, rich in other burial monuments and features, make this site nationally important. Significant monuments are also found elsewhere, however, such as the Neolithic long barrow at Whitwell.

The light and fertile soils of the ridge favoured settlement in this area at the onset of farming around 4,000 BC.

There is evidence that, from the Iron Age to well after the end of the Roman occupation, there was increased agricultural exploitation of the area with the use of ditches and banks to define settlements, stock pens, fields and tracks. In this period, the landscape had probably been cleared of much woodland and was occupied by single, quite widely spaced farmsteads with their associated field systems and ditched trackways leading outwards to the open pastures and woodland. Examples of important defensible hill forts remain from this period at Barwick in Elmet in the central section and Markland Grips in the south.

The Roman occupation had a major influence on the landscape as the ridge was a favoured location for the making of Roman roads along with military camps and settlements. The routes, later to become known as Ermine Street and Dere Street, were the basis for much of the route of the modern A1 which has a significant influence on the landscape today.

Arable-based open field farming, probably developed in the later Anglo-Saxon period, was extensive until the late 18th century, after which the present day pattern of large-scale fields and some dispersed farmsteads was established. Earlier small-scale and irregular enclosure patterns can still be seen around some villages.

In Yorkshire, Ripon developed as an ecclesiastical centre from the 7th century (the shrine of St Wilfrid), and in the 12th century as a planned borough with a market and church of collegiate canons, while in Derbyshire Bolsover was a planned 12th-century town outside the castle. The medieval period saw the pattern of nucleated settlements laid down, such as the market towns of Knaresborough and Pontefract, but a high number of deserted/shrunken settlements indicate a subsequent reduction in population from the high settlement levels of the early 14th century. Knaresborough originated as a medieval market centre between the Pennines and the Vale of York, and as a textile centre, until its decline from the early 19th century. Several dramatic defensive sites were established, especially overlooking the narrow gorges which acted as routes across the ridge, such as at Knaresborough, Conisbrough and Barlborough.

Wealthy landowners have also had a notable influence on the landscape by means of the fine buildings and designed parklands that they created from the 16th century. The wealth and resource range from the remains of the great abbeys, such as Fountains Abbey near Ripon, to the chain of country houses and designed parklands which runs along the ridge from Bedale Hall in the north to Hardwick Hall and Newstead Abbey, once home of Lord Byron, in the south. It includes the internationally renowned gardens at Studley Royal and estates such as Bramham, Ledston and Lotherton to the east of Leeds as well as Brodsworth, Cusworth and Melton Parks near Doncaster, with later estates based on the industrial wealth earned from surrounding areas. Some of these houses, parks and estates were created by wealthy industrialists involved in coal mining and steel making in areas to the west during the 18th and 19th centuries.

In the 19th and 20th centuries development followed the rivers, notably the Aire and the Don, as they were key trading routes between the North Sea and the industrial hinterland. Exploitation of deep coal resources at Maltby and Creswell led to industrial developments and settlements, while military installations and airfields were constructed along the line of the A1.

This narrow strip of land has been under considerable pressure from both industrial and residential development in recent years, leading to an expansion of towns such as Castleford, Doncaster and Hucknall. There has also been a significant increase in large warehouses, associated with the upgrade of the key north-south route of the A1, and its links with other motorways running east-west. These developments have led to a reduction in the extent of dark night skies and tranquillity.

Mineral workings have also had local impacts on the landscape, with limestone quarrying in central and southern areas (including around Whitwell), coal mining around Maltby, Creswell and Bolsover, and sand and gravel extraction in particular in the Ure and Swale corridors.

The landscape still remains dominated by agriculture, in particular arable production, with a recent reduction in livestock and dairying. Woodland cover has increased over time, with many small woodland parcels established throughout the area, and larger blocks in the south associated with the Greenwood Community Forest. However, traditional coppice management, which contributed to the diversity of woodland fauna including the dormouse, and flora have declined. Improved management of hedgerows in this area continues to enhance the landscape and the biodiversity within it.