Blaenavon Ironworks began production in 1789 with 3 furnaces. Two more furnaces were built c1810. The original partnership, led by the Hill family, sold the works in 1836 to the Blaenavon Iron and Coal Co. Initial investment at the site included the construction of a water balance lift for conveyance of pig iron from the site, but further investment did not occur until the 1850s. A new blast engine was built, and a new furnace was blown in during 1861. Investment was also made on a new site kown as Forgeside. By 1900 only one furnace remained in blast, but this was blown out in 1904. Thereafter the site was used by small-scale engineering companies until it became a guardianship monument.

The large shed was built before 1880 and was used for engineering purposes. The smaller shed is mid C20. Both were latterly used as garages.

A large single-storey shed of brick with a corrugated iron roof. The front (S) facing the yard has a wide doorway with iron lintel and double sliding doors. The NW angle is splayed. The smaller, later attached to the R side is also brick with a corrugated iron roof and sliding doors to the front.

R Hayman, Hayman & Horton, 6/1/2003