Forge and foundry are inseparable from the Haute-Marne. Initiated by the Cistercian monks around the 12th century, they developed in the 18th and 19th centuries. In 1850, a fifth of French cast iron production came out of the blast-furnaces of the Haute-Marne. The valleys of the Voire, Marne, Saulx, Ornain and Blaise rivers had up to twenty blast furnaces. In 1837, King Louis-Philippe authorised the building of a blast furnace at Sommevoire. Antoine Durenne bought it in 1857 and founded the Antoine Durenne Foundry. This was the beginning of the long saga of cast iron art that GHM continues to perpetuate today.