The remains of the blast furnace at the heart of the Carmarthen tinplate works (NPRN 40504), with an attached casting house, are preserved within a modern building.
The furnace may have been in operation as early as the mid eighteenth century. It was built into the slopes below the leat that powered the works, at the south-east end of a long range of buildings. The long range appears to survive in some form. The furnace is a massive structure built of regularly coursed stone rubble. There are furnace arches on the south-west and south-east sides. The casting house on the south-west survives as the lower two storeys of the modern three storey building. It is also stone-rubble built and retains some early features. There was originally a second casting house(?) on the south-east side.
To the north-east of the furnace the remains of a nineteenth century factory building survive within a modern warehouse (see NPRN 40504).
Furnace Lodge (NPRN 17572), on the far side of the Carmarthen road, was named for this furnace.

Source: CADW Listed Buildings (9448)

John Wiles 16.10.07