Description

The Hirwaun Ironworks dates from 1757 when John Maybery leased land at Hirwaun to erect a furnace. In 1780 the concern was leased to Anthony Bacon of Cyfarthfa. It is unclear as to whether Bacon was responsible for the conversion of the works from charcoal to coke, or whether this change in fact dated to the previous occupiers, the Maybery's. Either way, the ironworks were the first in Wales to use coke to fire the furnaces. After Bacon’s death in 1786 the lease of Hirwaun passed to Samuel Glover of Abercarn. Although the ironworks was assessed as producing 1,050 tons of iron in 1796, production seems to have seldom risen to over 10 tons per week. In 1805, when under the control of a new partnership the ironworks remained a single furnace affair, producing 450 tons of iron. The site was subsequently developed, and when the Hirwaun Ironworks was put up for sale in 1813 it comprised of two well constructed furnaces, two cast houses, an air furnace and two fineries, a blast engine on Boulton and Watt’s principle, with a blowing cylinder working through a water regulator, a forge with ten puddling furnaces and five balling furnaces and a Trevithick steam engine working two pairs of puddling and a pair of finishing rollers capable of rolling 80 to 100 tons weekly. Other property in the sale included a counting house, a further forge, pattern room, drying sheds, carpenters and smiths workshops, a waterwheel for turning a lathe for the rollers and grinding clay, a brick kiln, four calcining kilns, mineral yard, coke banks, two counting houses, three limekilns, four collieries, iron ore levels, cottages and tenements.

The site was unoccupied between 1814 and 1819, when William Crawshay of Cyfarthfa took over the lease. The two furnaces were rebuilt and a powerful 52½in. beam blowing engine constructed by the Neath Abbey Iron Company was installed. Output was improved, and the site was further expanded with more furnaces built in 1822. Output continued to rise with 7,020 tons of iron being produced in 1826 and 9,370 tons in 1830. The four furnaces continued in blast during the 1830s and 1840s, although Hirwaun was never a very profitable concern for any of its owners. During the mid 1850s relations between the Marquis of Bute, who owned part of the site, and Francis Crawshay became strained. The worsening relations had severe consequences for the works as the blast furnaces and mills were on Bute property with the furnace yard and limekiln on Crawshay property.

The furnaces were in blast for the first six months of 1859 after which the Crawshay's abandoned the site. The works reverted to the landowner, the Marquis of Bute, and in 1864 was leased to Handel Cossham and Thomas Challender Hinde who put two furnaces in blast. Between 1865 and 1866 when the works was under the control of the Hirwaun Iron and Coal Company the remaining two furnaces were repaired. However, operations were short lived and in 1867 the word ‘iron’ was dropped from the title of the company. When the Hirwaun Ironworks was advertised for sale in 1870 it was described as having four furnaces with a powerful blast engine, arrangements for utilising waste gases, hot air stoves, a spacious forge and mills with powerful engine, trains of rolls, nineteen puddling furnaces, forges and steam hammers. No interested parties came forward and the Hirwaun Coal Company was wound up.

The ironworks site remained unoccupied until 1880 when the Stuart Iron, Steel and Tin Plate Company took it over. The Hirwaun Ironworks was renamed the Stuart Ironworks and some improvements were made to the furnaces. However, little production of iron took place and the works later became a general foundry.

The site comprises four ruinous blast furnaces which survive as overgrown earthen mounds showing variable amounts of outer brickwork, both in situ and fallen. Aligned WNW-ESE they are separated from the charge bank by a blast passage. In addition to the ruins of the blast furnaces, the site retains a massive tramroad causeway and bridge. This high single-track causeway is approximately 100m in length and is carried over the Afon Cynon by a single span bridge with segmental arch and narrow dressed-stone voussoirs and coursed rubble revetments. The flat deck is a footpath retaining some stone sleepers. This structure was built 1806-8 by the engineer George Overton to replace an earlier bridge, sited immediately south of the present bridge, of a tramroad built in 1793, upon which raw materials were carried to the furnaces of Hirwaun ironworks and limestone was brought from the quarries at Penderyn.

The monument is of national importance for its potential to enhance and illustrate our knowledge and understanding of the development of the iron industry. An ironworks may be part of a larger industrial complex and their importance can further enhanced by their group value.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.

Source: Cadw