Hirwaun lies four miles north west of Aberdare in Rhondda Cynnon Taff, South Wales. The village sits to the south of the Brecon Beacons National Park, close to the Heads of the Valleys Road.
In 1911 a lake nearby, Llyn Fawr, was drained, and many historical artefacts were found. The Llyn Fawr hoard was discovered during the construction of a reservoir. It contained many objects from the late Bronze Age, but also a number of iron objects, notably an iron sword. Two other iron implements were found, a spear and a socketed sickle. Bronze items included two cauldrons and axeheads. The items appear to have been placed in the lake as votive offerings. The sword is thought to date from about 650 BC. It is the earliest iron object discovered in Wales.
In more recent times Hirwaun was known for its industrial background , the coal mines and the Hirwaun Ironworks. The ironworks were already in existence during the late 18th Century and passed through a succession of owners before being purchased in 1819 by William Crawshay of Cyfarthfa, in whose family it remained until closure in 1859. Famed for its products the Hirwaun works made cannons which were used on the HMS Victory.