North Rhine-Westphalia is Germany’s most populous state, with around 18 million inhabitants. Characterized by major cities like Köln and Düsseldorf, as well as rural regions such as the Sauerland and the Eifel, the state offers a diverse landscape. North Rhine-Westphalia is historically significant through cities like Aachen (coronation site of German kings) and Bonn (former capital). The Rhine-Ruhr metropolitan region is a central economic hub and one of the largest urban areas in Europe, having developed from an industrial to a service-based region. The state is defined by cultural differences between the Rheinland, Westfalen, and Lippe, and is home to numerous educational institutions.Wikipedia