47 - Southern Lincolnshire Edge : Description

Physical and functional links to other National Character Areas

To the north, the high, arable, limestone plateau continues through the Northern Lincolnshire Edge and Coversands National Character Area (NCA). There are many similarities between the two NCAs. The ridge of Jurassic Limestone that runs through them is part of a belt that runs from the Dorset Coast to the Humber Estuary. The Trent and Belvoir Vales NCA lies to the west, while the flat, drained land of The Fens NCA can be found to the east.

The River Witham rises south of Grantham, passes through Lincoln and drains to The Wash at Boston. The River Slea rises in this NCA at West Willoughby near Ancaster, and drains north-east into The Fens NCA to join the River Witham and eventually drain into The Wash. The Witham catchment features the Trent Witham Ancholme River Transfer Scheme. The limestone holds a regionally important aquifer and supplies water for industry, agriculture and domestic consumption.

There are a number of long-distance routes linking this to other NCAs: historic routes such as Ermine Street, a Roman road linking London to Lincoln and York; and walking routes such as the Viking Way, between Rutland Water and the Humber Bridge, which although created in the 1970s reflects the historic influence of Danelaw in the area.

Major road routes include the A15 linking Sleaford to Lincoln. Railways run east-west linking Sleaford to Boston and Nottingham, and north-south linking Sleaford to Lincoln and Spalding.

The Southern Lincolnshire Edge today

The landscape of the Southern Lincolnshire Edge National Character Area is one of an elevated, gently sloping plateau with a sharply defined western boundary in the form of a north-south cliff of Jurassic Limestone. The cliff is a dramatic linear feature, with a two-tier section in the south between Leadenham and Grantham. This is made up of a lower tier of ironstone, Lower Jurassic Marlstone Rock, separated from a higher tier of Middle Jurassic Lincolnshire Limestone by the softer Whitby Mudstone Formation. The higher land has fertile soils that support productive, largely arable agriculture in large, regular fields bounded by drystone walls. The landscape is an open one with relatively few trees and woodland and far-reaching views into the Trent and Belvoir Vales to the west and down the dip slope to the fens in the east. Cropping is predominantly cereals, but also sugar beet and potatoes. On lower land to the south-west and the eastern edge, where the dip slope falls to meet the fens, deposits of glacial till result in heavier land that is slower draining and prone to waterlogging in winter. This landscape has a more enclosed, wooded feel, with smaller, less regular fields and more hedgerows, hedgerow trees, parkland and woodland. The heavier land supports more livestock grazing pastures and more mixed farms than on the higher, more freely draining plateau.

Watercourses occur along the cliff edge where the porous limestone meets seams of less permeable clay. Streams also rise on the dip slope and drain into the fenland to the east, the River Slea being the biggest of these. The River Witham cuts through the limestone cliff just south of Lincoln. Dry valleys indicate the free-draining nature of the underlying geology. The agricultural land has a dense network of ditches, particularly on the heavier land, and many have farm reservoirs. There are no water company reservoirs in the area and few natural ponds or lakes, due to the permeable nature of the soils across much of the area. However, the limestone holds a regionally important aquifer and supplies water for industry, agriculture and domestic consumption.

Semi-natural habitats are fragmented and sparsely scattered within the Southern Lincolnshire Edge NCA. Verges along roads, tracks and Roman roads provide a valuable refuge for flower-rich limestone and neutral grassland. These habitats support many species of rare plants and in turn provide valuable habitats, food sources and movement corridors for butterflies, insects and other wildlife. Some of the arable land is of great value for arable birds, particularly skylark, lapwing, corn bunting, grey partridge, yellow wagtail, tree sparrow and turtle dove, which use it for nesting and feeding. The River Witham supports white-clawed crayfish. Woodland is primarily composed of oak and ash, interspersed with wild service tree, cherry, aspen and field maple. There are important areas of ancient limewoods on the north-east fringe, along the border with The Fens NCA.

The cliff and the high land to the east of it retain numerous prehistoric and Roman sites, such as the bronze-age triple ditch system at Honington and Ermine Street Roman road. Ridge and furrow is well preserved in some places to the east, under uncultivated grassland. This lower-lying, wetter landscape on the margins of the fens also preserves archaeological features such as Car Dyke Roman drainage channel and several medieval moated sites and fish ponds. The high incidence of medieval defensive sites suggests this area was once regarded as a frontier. The south-west corner of the NCA between Sleaford and Grantham includes several parklands, including Belton Park and Rauceby Park.

Settlement is concentrated around the perimeter of the NCA, along the cliff foot, where villages have been founded on springlines, and at the foot of the dip slope, where the larger conurbations such as Sleaford lie. Many of the villages retain their traditional character, with buildings of local limestone and pantile roofs. Villages to the east of the dip slope tend to be in elongated parishes that stretch between the wetter lowlands suitable for grazing and the higher, drier land better suited for arable cropping. Some manor houses and estates occupy sheltered locations looking up at the cliff, such as Leadenham.

Industry in the area, both historically and today, focuses on limestone and aggregate quarrying and agriculture. Major transport links include busy A roads, such as the A15 between Lincoln and Sleaford, and railway lines running north-south and east-west. Publicly accessible routes and areas are less prolific than in some NCAs; there are only 0.9 km per km2 of public rights of way and no country parks or National Nature Reserves. However, there are long-distance routes such as the Viking Way, 311 ha of publicly accessible land, and a number of parklands – such as Belton – that are open to the public. The area is moderately tranquil; less-disturbed areas include the more remote parts of the sparsely settled areas, the open landscape of the dip slope and the more sheltered, enclosed, traditional landscapes of the claylands, with the area around Sleaford being the most disturbed.

The landscape through time

The limestone that so dramatically defines this area in terms of landform, vegetation and building materials was part of a succession of limestones and mudstones that were laid down across the area during the Jurassic Period, 195-145 million years ago. These rocks and the fossils that they contain provide evidence that they were deposited in shallow tropical seas with reefs, sandbars, tidal lagoons and coastal swamps. During the Pleistocene (1.8-0.01 million years ago) the area was affected repeatedly by glaciation. The ice sheets left tills (boulder clay) that are particularly evident in the southern and eastern parts of the NCA, forming the heavy clay soils of those areas. Meltwater released from the glaciers carried sand and gravel that was deposited in channels below the glaciers or in outwash plains in front of them.

It is thought that the higher land of the dip slope would have been cleared of trees in the early Neolithic. Its free-draining nature would have been attractive to early settlers and would have provided a valuable dry overland route away from the marshy and densely wooded lowlands on either side (East Midlands Regional Landscape Character Assessment, East Midlands Landscape Partnership, 2010). Visible reminders of early settlement are widespread, including prehistoric burial mounds, linear boundary features and trackways. Roman activity is visible in structures such as Car Dyke Roman canal, the marching camp at Sudbrook and Ermine Street.

Place names suggest that villages were of Scandinavian or Saxon origin. Saxon and medieval settlement developed in a series of small villages along the springlines on the western scarp, and on the lower claylands of the dip slope to the east. Archaeological and placename evidence suggests that the area was substantially cleared of woodland by the 11th century and, on higher land, largely unsettled heath was used as common grazing until it was enclosed for farmland from the late 18th century. Medieval and Tudor estates testify to the wealth derived from wool production, the heathlands providing common pastures for sheep, as well as rabbit warrens.

The marginal nature of the soils before improvement and enclosure in the 18th and 19th centuries meant they would have been of limited agricultural productivity, which perhaps contributed to the abandonment of some of the medieval villages in the area, combined with the devastating effect of the Black Death. Enclosure of fields from the common land under the Parliamentary Enclosures Acts of the 18th and 19th centuries resulted in a large-scale regular field boundary network away from the villages. Ermine Street continued to play an important role and influenced the layout of enclosures. Scattered farmsteads were built at this time, typically with combination barns serving cattle courts, although some may have originated as monastic granges or specialist sheep farms in the medieval period. Parklands associated with the country houses of major landowners are found on both sides of the Edge (Lincolnshire Cliff) along its entire length, and in the 19th century estates were responsible for the development of estate villages as well as farmsteads.

The open, reasonably flat ground near the escarpment, with strong prevailing winds to aid take-offs and landings, meant this landscape was well-suited to the selection of sites for airfields, most famously at Cranwell, which was developed from its origins in the First World War to the Royal Air Force’s (RAF’s) main officer training school. Waddington and other bomber bases were established after 1934 and expanded during the Second World War and the Cold War. Many of the airfields are no longer in use, but some retain runways, hardstandings, bomb dumps and buildings.

The latter half of the 20th century saw widespread agricultural intensification, involving comprehensive drainage schemes, removal of drystone walls and hedgerows to create bigger fields, and an increase in arable production. It also saw an increase in the size of the major settlements and the upgrading of major transport routes. All of these served to reduce and fragment semi-natural habitats. In the 21st century agri-environment schemes have helped to fund the maintenance, enhancement and restoration of traditional field boundaries, semi-natural habitats and historic features such as archaeological earthworks and traditional farm buildings.