Blaenavon Ironworks is the most historically significant feature in the UNESCO World Heritage site of Blaenavon Industrial Landscape.
Having begun production in 1789, the ironworks is the best-preserved blast furnace complex of its period and type in the world and one of the most important monuments to have survived from the early part of the Industrial Revolution.
It was one of the most important producers of iron in the world and the site of experiments by metallurgist and inventor Sidney Gilchrist Thomas and his cousin Percy Gilchrist. In 1875, Thomas discovered how to eliminate phosphorus, a major impurity in some iron ores, in the Bessemer converter.
The method is now called the Thomas-Gilchrist process, the Thomas process, or The Basic Process.
Today you can view the extensive remains of the Water Balance Tower, blast furnaces, company shop and workers’ cottages at Stack Square and Engine Row, all painstakingly restored and managed by Cadw Welsh Historic Monuments. Cutting-edge audio post technology is also used to help bring the story of Blaenavon Ironworks to life, The ironworks itself, though, is only a part of the story. The surrounding landscape is also revolutionary in its form and function. From mines to tram lines, you can still trace the routes in and out, from raw material to finished product.