The Sillon industriel (French for "industrial valley") is the former industrial backbone of Belgium. It runs across Wallonia, passing from Dour, the region of Borinage, in the west, to Verviers in the east, passing along the way through Mons, La Louvière, Charleroi, Namur, Huy, and Liège. It follows a continuous stretch of valleys of the rivers Haine, Sambre, Meuse and Vesdre, and has an area of roughly 1000 km².