The exact date for the first smelting of iron in the valley is not known, but it could have been back in the reign of Queen Elizabeth I before 1600.
Records show that a Mr Brunton of London constructed a furnace at Ynyscedwyn in 1628. Other furnaces were built on the site over the years and by 1717 the works were producing about 200 tons of iron each year using local iron ore, limestone from the Cribarth, and smelting with charcoal transported by packhorse.

As all these materials were hauled by horses over rough roads this limited what could be produced. In 1750 the furnace at Ynyscedwyn was one of seven in South Wales.

In 1788 the owners of the Ynyscedwyn ironworks leased the works to Joseph Parsons, an ironmaster from Cadoxton. He developed the site using coal brought up the valley instead of charcoal. The local hard coal called anthracite could not be used as it did not burn well in the furnaces. Even so, production increased to 800 tons per year at the Ynyscedwyn forge, and cannonballs for the armed forces were made there.
The map above shows the Ynyscedwyn forge in 1794.

More on the story of iron smelting...