Gunns Mill Furnace

Forest of Dean, Gloucestershire

Scheduled Monument, at risk


The Forest of Dean has a long history of iron making, and in the Middle Ages was the premier iron-making district in Britain. For part of the 17th century it had more charcoal fuelled blast furnaces and forges than anywhere else in the country, and Gunns Mill was one of them.

The furnace is a rare and important survival, considered one of the most impressive sites of its kind in England, as so much remains, including the original timber charging house and the half-timbered paper drying house dating from the 18th century.

Gunns Mill Furnace is one of the most complete surviving 17th century blast furnace in the country. The raw materials used to produce cast iron were iron-ore, slag from bloomeries (old iron-works) and charcoal. The iron from the furnace was then refined in chafery and finery forges to become wrought iron, usually in bar form. Molten iron from the furnace will also have been cast into moulds for items such as fire backs.


The furnace sits on a strong tributary of the Westbury Brook, in the Flaxley Valley, and occupies a site that was used by corn and fulling mills from at least 1435. The place-name derives from the clothier William Gunn, who leased the mill in 1596, presumably for fulling cloth.  Around 1625, a blast furnace was built, almost certainly by Sir John Winter, ironmaster of Lydney. Sir John was a grandson of Drake’s associate, Admiral Winter.  He was also secretary to Queen Henrietta Maria.

Winter forfeited his estates during the Civil War and the furnace was seized in 1644 by John Brayne. By 1653 Winter regained his lands and the furnace. After 1680, the furnace was rebuilt by the iron masters Scudamore of Herefordshire, and Hall of Highmeadow, near Coleford. The cast iron lintels carry the dates 1682 and 1683. Dendrology dating has revealed that the oak trees used for the beams of the superstructure adjoining (but not above) the furnace were felled in 1681-82 and thus formed part of the rebuild. The survival of a 17th century furnace superstructure is unique in Britain.

In 1702, Gunns Mill was purchased by Thomas Foley of Stoke Edith. Under the Foley Partnership, cast iron was produced there until 1736 – it produced 779 tons in 1705-6.  Iron making ended here sometime between 1736 and 1741, but iron making with newer methods continued in Dean long after Gunns Mill was blown out.

Conversion to a paper mill

In 1741, Joseph Lloyd founded a paper works, presumably using the water wheel to power hammers to crush rags, and a half-timbered structure was built on top of the furnace itself, next to the adjoining charging house, for drying the paper produced below.  For access, a staircase was built inside the shaft of the furnace, and although this meant making holes in the side of the furnace it led to preservation of much of the interior under plaster.  Paper making was continued by Lloyd’s descendants until 1840 - they also owned the paper mills at Postlip near Winchcombe.  After 1842, paper making at Gunns Mill was continued by others, with steam power added in 1851.  Production ceased in 1879 and the buildings were afterwards used by farmers.  The fine mill house was reduced from three storeys to two. The pond was infilled and many of the ancillary buildings were demolished or fell down. Increasing dilapidation continued despite a Building Preservation Order being made in 1968 following pressure for action from Dr Cyril Hart.


The site was listed Grade 2* in 1955.  The listing states:

SO 61 NE LITTLEDEAN Mill at Gun's Mills 6/67 (formerly Listed as Barn at Gunn's Mills, East Dean Parish) 23.9.55 GV II*

Formerly blast-furnace, later paper mill, now unused. 1682/3 (on iron lintels), mid C18. Coursed, squared rubble to furnace and blowing chamber, ashlar dressings and corrugated-iron roof to latter; upper building part rubble stone, part timber-framed, with slate roof. 'L' plan, pivoted on furnace, wings at different levels. Square blast-furnace at lower level, with tapering recess in main face, roof sloping back to main wall line, with 2 iron lintels. Doors at ground floor and in sloping face above. This recess repeated on left return, in blowing chamber, with dated lintels. Inside square chamber with sloping walls above 2m. Narrow top now covered by stone slab in floor of room above. Blowing chamber on left with opening against furnace, then 2 windows, unclosed: upper part of wall rebuilt in concrete block, (originally 2 floors). Behind pit, 7.5m long for overshot water- wheel: small arched recess in back wall. Space in front of furnace and blowing chamber was casting floor. Upper level at right-angles; timber-framed over furnace, 3-bays, built as paper mill. Wattle and daub infill to gable wall, open or glazed sides in 2 panels per bay: partition to stone section beyond, 3 bays, with floor over at eaves level. Trusses queen strut. Stone section 2 large openings in gable, one in side leading to 4-bay wing. Furnace originally built 1628, probably destroyed 1650; rebuilt 1682/3. Converted to papermill by 1743, and so used to at least 1900: furnace became stairs. Mill pond lay beyond house now filled in. Considered to be 'best remaining furnace of the earliest phase of British blast-furnace practice'. (C. Hart, The Industrial History of Dean, 1971, p. 43, 70, 379).

The site today

In the 1980s the site and Gunns Mill House changed hands. In 1986 the site was scheduled by English Heritage. Subsequently Ancient Monument and Listed Building Consent were granted for conversion of the building into a two-bedroomed dwelling. Learning of this, William Parker purchased the furnace and the adjacent land in 1994 to prevent such development.  He put up shoring externally and scaffolding internally to prevent its collapse, as by this time the structure was in poor condition and the scale of work needed for preservation was large.  Subsequently, English Heritage, although unwilling to take it into Guardianship, inserted major scaffold shoring and weatherproofed the structure. The dating of the oak timbers has increased the historic value of the site from important to unique, but for more than a decade Gunns Mill Furnace has remained shrouded in white plastic and it continues to deteriorate, albeit at a slower rate than previously.  It is high on the English Heritage Monuments at Risk Register.

The conservation of Gunns Mill was always destined to be high on the agenda of any organisation interested in the care of our local heritage.  The challenge has been the cost of the work necessary and the identification of an end use.  The Trust is now seeking to address this challenge.

Current activity

William Parker donated Gunns Mill to the Forest of Dean Buildings Preservation Trust in 2013.  Response to the Trust’s involvement has been very positive from the Forest of Dean District Council, English Heritage and other relevant institutions, and significant financial assistance has been received, principally from the Gloucestershire Environmental Trust, to assist in conservation of the site and the preparation of plans for restoration of the structure.  Initial work has involved surveys of various kinds, and establishing and fencing the boundaries.






© 2014 Forest of Dean Buildings Preservation Trust

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