The city of Liege in Belgium has a long and rich history in steel production. From the factory founded by John Cockerill in Seraing in 1817, through various mergers and the eventual takeover of the company by ArcelorMittal, to the dismantling of the last two blast furnaces in 2011. For more than a century, thousands of men toiled in the factories, forges, and foundries. The remnants of this industry are all over Seraing and Ougrée, serving as silent witnesses to a changing economic landscape.

The historic buildings and structures are rapidly disappearing, some are being redeveloped, most are being demolished. "Acier / rouille", French for "steel / rust", focuses on these neglected and disappearing places, analytically depicting the endless complexity and variety in the installations and factories.