Especially in the Haine, Sambre and Meuse valleys, between the Borinage and Liège, where there was a huge industrial development based on coal-mining and iron-making, urbanisation was fast.
Især i Haine, Sambre og Meuse dalene mellem Borinage og Liège, hvor der skete en enorm industriel udvikling baseret på kulminer og jernfremstilling, foregik der en hurtig urbanisering.