Scowle

Scowles are landscape features which range from amorphous shallow pits to irregular labyrinthine hollows up to several metres deep. and are possibly unique to the Forest of Dean in Gloucestershire, England.

They have traditionally been interpreted as the remains of prehistoric and early historic open-cast iron ore extraction, but investigation undertaken by the Forest of Dean Archaeological Survey from 2003 to 2004 suggests that they have a primarily natural origin which has been exploited by humans.

Scowles have developed over millions of years. They occur in a broken ring around the central part of the Forest of Dean, and are confined to particular geological outcrops of carboniferous limestone and sandstone. Ancient cave systems were formed underground, before iron-rich water from the coal measures of the central Forest area permeated from the surface and deposited iron ore in crevices. The caves were then uplifted, eroded and exposed as a surface of deep hollows and exposed rock.

Much later, humans — certainly from the Iron Age and later in the Roman period — recognised that iron ore could be found in veins and pockets in the exposed rock faces. In some places, when the surface exposures were exhausted they followed veins of iron ore underground. The ore was then smelted locally, using locally obtained charcoal, and made into objects or traded, by way of the River Wye or ports on the River Severn and its estuary. However, there is little direct evidence for dating the exploitation of iron ore from scowles.

The most likely origin of the word "scowle" is that it derives from a Brythonic word crowll meaning a cave or hollow, or the Welsh word ysgil meaning a recess. Welsh was the main language in the local area before about the 9th century.

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