Germany is divided into 16 federal states, or Länder, from Bavaria and Baden-Württemberg in the Alpine south to Schleswig-Holstein in the Baltic north, including industrial states such as North Rhine-Westphalia, Hesse, and Saxony. It is Europe´s largest economy, with a GDP of more than €4 trillion, and its network of autobahns connects industrial regions such as the Ruhr with financial centers such as Frankfurt and ports such as Hamburg and Bremen. Bavaria is the largest state, covering 70,550 square kilometers and home to 13.3 million inhabitants, while North Rhine-Westphalia is the most populous, with more than 18 million. In this Risk, the northern plain is a zone of rapid advance toward Poland and the Netherlands, the Bavarian Alps are a fortified southern border toward Austria and Switzerland, and controlling the Rhine-Ruhr axis gives you access to industrial resources, energy, and routes toward France, Belgium, and the North Sea. The Berlin-Brandenburg corridor is key to the east, and whoever controls the southern states such as Bavaria and Baden-Württemberg controls the border with Central Europe and the Balkans.