The Weald is the name given to a physiographic area in south-east England situated between the parallel chalk escarpments of the North and the South Downs. It should be regarded in two separate parts: the sandstone "High Weald" in the centre; and the clay "Low Weald" periphery. The name, Saxon in origin, signifies woody country, which still applies today: scattered farms and villages betray The Weald‘s past, often in their names.
The adjective for "weald" is "wealden".
The Weald is the eroded remains of a geological structure, an anticline, a dome of layered Lower Cretaceous rocks cut through by weathering to expose the layers as sandstone ridges and clay valleys. The oldest rocks exposed at the centre of the anticline are correlated with the Purbeck Beds of the Upper Jurassic. Above these, the Cretaceous rocks, include the Wealden Group of alternating sands and clays - the Ashdown Sand, Wadhurst Clay, Tunbridge Wells Sand (collectively known as the Hastings Beds) and the Weald Clay. The Wealden Group is overlain by the Lower Greensand and the Gault Formation, consisting of the Gault Clay and the Upper Greensand.
The rocks of the central part of the anticline include hard sandstones, and these form hills now called the High Weald. The peripheral areas are mostly of softer sandstones and clays and form a gentler rolling landscape, the Low Weald. The Weald-Artois Anticline continues some 65 km (40 miles) further south-eastwards under the Straits of Dover, and includes the Boulonnais of France.
Many important fossils have been found in the sandstones and clays of the Weald, including for example Baryonyx. The famous scientific hoax of Piltdown Man was claimed to have come from a gravel pit at Piltdown near Lewes. The First Iguanodon was identified by a Lewes Doctor Gideon Mantell in 1819 from a pit near Cuckfield.
Prehistoric evidence suggests that, following after the Mesolithic hunter-gatherers, the Neolithic inhabitants had turned to farming, with the resultant clearance of the forest. With the Iron Age came the first use of the Weald as an industrial area. Wealden sandstones contain ironstone, and with the additional presence of large amounts of timber for making charcoal for fuel, the area was the centre of the Wealden iron industry from then, through the Roman times, until the last forge was closed in 1813. The index to the Ordnance Survey Map of Roman Britain lists 33 iron mines: 67% of these are in the Weald.
The entire Weald was originally heavily forested. Over the centuries deforestation for the shipbuilding, charcoal, forest glass, and brickmaking industries has left the Low Weald with only remnants of that woodland cover.
Settlements on the Weald are widely scattered, and villages as such did not appear until the 13/14th centuries. Before this time, the Weald was used as summer grazing land, particularly for pannage by communities living in the surrounding areas. Many places within the Weald have retained names from this time, linking them to the original communities by the addition of the suffix "-den" – for example Tenterden was the area used by the people of Thanet. Permanent settlements in much of the Weald developed much later than in other parts of lowland Britain, although there were as many as one hundred furnaces and forges operating by the later 16th century, employing large numbers of people.
Much of the High Weald, the central part, is designated as the High Weald Area of Outstanding Natural Beauty. Its landscape is described as one of rolling hills, studded with sandstone outcrops and cut by streams to form steep-sided ravines (called gills); small irregular-shaped fields and patches of heathland, abundant woodlands; scattered farmsteads and sunken lanes and paths. Remnants of a possible Royal forest (the chace) exist today as Ashdown Forest.
There are centres of settlement, the largest of which are Horsham, Burgess Hill, East Grinstead, Haywards Heath, Tonbridge, Tunbridge Wells, Crowborough; and the area along the coast from Hastings and Bexhill-on-Sea to Rye and Hythe.
The geological map shows the High Weald in lime green (9a).
The Low Weald, the periphery of the Weald, is shown as darker green on the map (9), and has an entirely different character. It is in effect the eroded outer edges of the High Weald, revealing a mixture of sandstone outcrops within the underlying clay. As a result, the landscape is of wide and low-lying clay vales with small woodlands (“shaws”) and fields. There is a great deal of surface water: ponds and many meandering streams.
Some areas, such as the flat plain around Crawley, have been utilised for urban use: here are Gatwick Airport and its related developments and the Horley-Crawley commuter settlements. Otherwise the Low Weald retains its historic settlement pattern, where the villages and small towns occupy harder outcrops of rocks. There are no large towns on the Low Weald, although Ashford and Reigate lie immediately on the northern edge. Settlements tend to be small and linear, because of its original wooded nature and heavy clay soils.
The Weald is drained by many streams radiating from it, the majority being tributaries of the surrounding major rivers: particularly of the Mole, Medway, Stour, Rother, Cuckmere, Ouse, Adur and Arun. Many of those streams provided power to watermills, blast furnaces and hammers which once operated the iron industry and cloth mills.
Although common in France, the wild boar became extinct in Great Britain and Ireland by the 17th century, but wild breeding populations have recently returned in the Weald, following escapes from boar farms.