The Haigh Foundry was an ironworks and foundry in Haigh, Lancashire, which was notable for the manufacture of early steam locomotives.
The Haigh Foundry was established in the Douglas Valley in Haigh around 1790 by Alexander Lindsay, 6th Earl of Balcarres and his brother Robert, as an ironworks and foundry. The ironworks was not a success but the foundry was, particularly after Robert Daglish became chief engineer in 1804, and the works acquired a reputation for manufacturing winding engines and pumping equipment for the coal mining industry. The foundry was leased by E.Evans and T.C.Ryley in 1835 for 21 years. The partners intended to produce railway locomotives and were later joined by a Mr Burrows.
In 1855 Haigh Foundry and Brock Mill Forge were offered for lease. They had manufactured some of "the largest pumping engines and the most powerful factory engines in the kingdom" in the previous decade. The iron works, on the bank of the River Douglas, consisted of a foundry, five cupola furnaces, three air furnaces for making the largest castings and another foundry for smaller pieces. Also on site were blacksmiths' and pattern-makers' shops, office, drawing shop, the foreman's house, boiler yard and iron warehouse. A water wheel driven by the river powered the machinery, line shafts and furnace blasts. The forge was powered by water and steam. Part of the works where spade making was carried out had Naysmyth steam hammers and a rolling mill. Also for lease was the firebrick and tile works which used fire clay from a nearby pit and had a kiln, drying sheds and a steam powered grinding wheels. The manager's house and cottages for workers were part of the lease. A railway line connecting it to the Lancashire and Yorkshire and London and North Western Railways was being built.