Details

The monument lies around 3km south west Of Oswestry and to the west of a minor
road. It includes the earthworks and buried remains of the Trefarclawdd
colliery, including shaft mounds, gin circles, water management features and a
trackway. The monument preserves the remains of a once-typical lowland mine
complex.

The Trefarclawdd colliery was in operation by 1792, and continued for around
40 years before flooding forced its closure in the 1830s. Throughout its
working life, horse-power was used to power drainage and winding machinery.
Trefarclawdd fell out of use without ever apparently installing steam engines,
and so its remains provide evidence for the layout of a typical late 18th
century colliery which employed horse-power.

Visible remains include a number of well-preserved shaft mounds with
associated spoilheaps and earthworks. The mounds are typically 2m high and 7m
wide, with a central depression surrounded by a collar of spoil. In some
cases, notably on a mound in the centre of the site, this collar forms a
flattened 2m wide surface or `gin circle' on which the horse would walk around
the shaft, powering the drainage or winding gear. A smaller shaft mound in the
south of the site is thought to be a ventilation shaft, cut to encourage the
circulation of air in deeper workings. There are spoilheaps of varying size
and shape in all areas, including a large dispersed heap of around 2m in
height in the eastern part of the site. Running roughly NNE-SSW in the western
part of the site, a 1.5m wide flat area between the mounds represents a
trackway and is further defined by shallow linear spoilheaps along its north
eastern edge. Spoilheaps are also visible around deep curving drainage cuts in
the northern and south eastern parts of the site. These cuts are part of a
water management scheme which took water from a nearby spring, diverting it,
and surface water, away from the mine workings to brick works and a pottery.

The brick works and pottery are believed to have stood in an area now covered
by farm buildings, and are not included in the scheduling. The monument will
retain the buried remains of pit-head mechanisms such as windlasses and
pumping engines, and underground remains will retain technological information
about extraction and haulage methods employed at the site. Further shaft
mounds visible to the east of the monument are not included in the scheduling.

All fence posts are excluded from the scheduling, although the ground beneath
them is included.

MAP EXTRACT
The site of the monument is shown on the attached map extract.

Source: Historic England

Reasons for Scheduling

Coal has been mined in England since Roman times, and between 8,000 and 10,000
coal industry sites of all dates up to the collieries of post-war
nationalisation are estimated to survive in England. Three hundred and four
coal industry sites, representing approximately 3% of the estimated national
archaeological resource for the industry have been identified as being of
national importance. This selection, compiled and assessed through a
comprehensive survey of the coal industry, is designed to represent the
industry's chronological depth, technological breadth and regional diversity.
The term `nucleated' is used to describe coal mines that developed as a result
of increased capital investment in the 18th and 19th centuries. They are a
prominent type of field monument produced by coal mining and typically
consist of a range of features grouped around the shafts of a mine. The
simplest examples contain merely a shaft or adit with associated spoil heap.
Later examples are characterised by developed pit head arrangements that may
include remains of engine houses for pumping and/or winding from shafts,
boiler houses, fan houses for ventilating mine workings, offices, workshops,
pithead baths, and transport systems such as railways and canals. A number of
later nucleated mines also retain the remains of screens where the coal was
sized and graded. Coke ovens are frequently found on or near colliery sites.
Coal occurs in significant deposits throughout large parts of England and this
has given rise to a variety of coalfields extending from the north of England
to the Kent coast. Each region has its own history of exploitation, and
characteristic sites range from the small, compact collieries of north
Somerset to the large, intensive units of the north east. A sample of the
better preserved sites, illustrating the regional, chronological and
technological range of nucleated coal mines, together with rare individual
component features are considered to merit protection.

The remains of the Trefarclawdd colliery survive well. The gin circles and
shaft mounds in particular are unusually well-preserved. The monument will
offer valuable technological data about methods of extraction, winding,
pumping and transport at a typical horse-powered colliery, contributing to our
understanding of Trefarclawdd colliery's development.

Source: Historic England