Occupation of the Ruhr important harbour in Duisburg-Ruhrort, ending French occupation of the Ruhr region on 25 August 1925. According to Sally Marks, the occupation of the Ruhr "was profitable and caused neither the German hyperinflation, which began in 1922 and ballooned because of German responses to the Ruhr occupation, nor the franc's 1924 collapse, which arose from French financial practices and the evaporation of reparations". Marks suggests the profits, after Ruhr-Rhineland occupation costs, were nearly 900 million gold marks. Despite his disagreements with Britain, Poincaré desired to preserve the Anglo-French entente and thus moderated his aims to a degree. His major goal was
Ruhr breaks between the individual city boroughs. Thus the Ruhr is described as a polycentric urban area, which shares a similar history of urban and economic development. Because of its history, the Ruhr is structured differently from monocentric urban regions such as Berlin and London, which developed through the rapid merger of smaller towns and villages with a growing central city. Instead, the individual city boroughs and urban districts of the Ruhr grew independently of one another during the Industrial Revolution. The population density of the central Ruhr is about 2,100 inhabitants per square kilometre (about 5,400 per square mile)—low compared