Reasons for Designation
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.
Coking is the process by which coal is heated or part burnt to remove volatile
impurities and leave lumps of carbon known as coke. Originally this was
conducted in open heaps, sometimes arranged on stone bases, but from the mid-
18th century purpose built ovens were employed. By the mid-19th century two
main forms of coking oven had developed, the beehive and long oven, which are
thought to have been operationally similar, differing only in shape. Coke
ovens were typically built as long banks with many tens of ovens arranged in
single or back to back rows, although stand alone ovens and short banks are
also known. They typically survive as stone or brick structures, but earth-
covered examples also exist. Later examples may also include remains of
associated chimneys, condensers and tanks used to collect by-products. Coke
ovens are most frequently found directly associated with coal mining sites,
although they also occur at ironworks or next to transport features such as
canal basins.
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. All surviving pre-
1815 ovens are considered to be of national importance and merit protection,
as do all surviving examples of later non-beehive ovens. The survival of
beehive ovens is more common nationally and a selection of the better
preserved examples demonstrating the range of organisational layouts and
regional spread is considered to merit protection.
The spread of railed transport and the increasing demand for coke in iron
production in the second half of the 19th century led to the founding of
numerous coke works at collieries in the North East Coalfield. The Hedleyhill
Colliery and coke works is typical of this movement. The development of the
coke industry in County Durham led to innovations in the methods of production
and oven design, and led to the widespread introduction of the bee-hive oven.
This design was pioneered in, and became characteristic of, the North East
Coalfield. The coke ovens at Hedleyhill illustrate this design and are now one
of only a small number of sites nationally where the scale of a large
installation of coke ovens and technological processes can be interpreted.
In addition, the surviving extent of the oven ranges at the site is one of the
most complete examples in the North East Coalfield.
Details
The monument is situated in the upper reaches of the Deerness Valley, 150m
south east of Hedleyhill Colliery village, and includes the ruins, earthworks
and buried remains of a late 19th century coke works. It was once part of the
Hedleyhill Colliery which is now largely cleared and landscaped and is not
included in the scheduling.
The colliery and coke works were in operation from at least 1879 under the
ownership of the Weardale Iron and Coal Company. Almost all of the colliery's
production, at least in the early years, was transported direct to the coke
works. By the mid-20th century the colliery had become uneconomic and was
finally abandoned in 1950.
The monument includes the best-preserved remains of the Hedleyhill coke works,
including the remains of two ranges of coke ovens, one double and one single,
of the beehive design developed in, and once typical of, the Durham coalfield.
The ovens consist of brick built domes, typically 3.58m in diameter, insulated
by an earthen bank. The remains of small top central holes and back flues
survive in many of the ovens. A number of the ovens survive to original height
and a little over half the circumference remains in the most complete
examples.
The remains of an additional double range located to the west are now very
fragmentary and difficult to interpret, and they are not, therefore, included
in the scheduling.
Little remains of the adjacent Hedleyhill Colliery site and its associated
transport system, though the more substantial domestic buildings of the
colliery village continue to be occupied. This is therefore not included in
the scheduling.
All modern fenceposts are excluded from the monument, although the ground
beneath these features is included.
MAP EXTRACT
The site of the monument is shown on the attached map extract.
It includes a 2 metre boundary around the archaeological features,
considered to be essential for the monument's support and preservation.
