Düsseldorf[a] is the capital city of North Rhine-Westphalia, the most populous state of Germany. It is the second-largest city in the state after Cologne and the sixth-largest city in Germany,[b] with a 2022 population of 629,047.[7] The Düssel, from which the city and the borough of Düsseltal take their name, divides into four separate branches within the city,[c] each with its own mouth into the Rhine (Lower Rhine). Most of Düsseldorf lies on the right bank of the Rhine, and the city has grown together with Neuss, Ratingen, Meerbusch, Erkrath and Monheim am Rhein. Düsseldorf is the central city of the metropolitan region Rhine-Ruhr, the second biggest metropolitan region by GDP in the European Union, that stretches from Bonn via Cologne and Düsseldorf to the Ruhr (from Duisburg via Essen to Dortmund).