The last 150 years of history of the extensive territory that goes from the source of the Llobregat river, in Castellar de n'Hug, to its mouth, in El Prat de Llobregat, have been marked by the pace of transformation and urbanization of the industrial colonies. The colonies are groups that are born, grow and develop in very different ways and that have turned the valley into a heritage space of the first order and, at the same time, complex: