In the beggining of the20th century, Belval was very different to the modern place to work and live we know today.
According to belval.lu,
The Escher Bësch forest is cleared to make way for one of the most modern steelworks of the time. From the ore dressing to the finished end product – with blast furnaces, steelworks and rolling mill, the plant carries out every stage in the production of steel. In 1913, more than 3000 steelworkers produce 400,000 tonnes of cast iron, 360,000 tonnes of steel and 297,000 of rolled products.