Berlin is the capital city of Germany and one of the 16 states (Länder) of the Federal Republic of Germany. Berlin is the largest city in Germany and has a population of 4.4 million within its metropolitan area and 3.5 million from 190 countries within the city limits. Berlin is best known for its historical associations as the German capital, internationalism and tolerance, lively nightlife, its many cafes, clubs, and bars, street art, and numerous museums, palaces, and other sites of historic interest. Berlin's architecture is quite varied. Although badly damaged in the final years of World War II and broken apart during the Cold War, Berlin has reconstructed itself greatly, especially with the reunification push after the fall of the Berlin Wall in 1989. It is now possible to see representatives of many different historic periods in a short time within the city center, from a few surviving medieval buildings near Alexanderplatz, to the ultramodern glass and steel structures in Potsdamer Platz. Because of its tumultuous history, Berlin remains a city with many distinctive neighborhoods. In Berlin there is more than one downtown area. Berlin has many boroughs (Bezirke), and each borough is composed of several localities (Kieze) — each of these boroughs and localities have their unique style. Some boroughs of Berlin, as noted below, are more worthy of a visitor's attention than others. Originally Berlin was officially divided into 23 boroughs, and these boroughs are still used in Wikitravel as they remain foremost in popular conceptions of the city and are generally of a good practical size and cultural division for visitors as well. Since January 2001, the boroughs have officially been reduced from 23 to 12 for administrative efficiency.