The german capital, one of the largest cities in Germany, with far over one million inhabitants. It's a state (Bundesland) on its own. Berlin is known not only for its important role in recent history, being parted in East Berlin and West Berlin by the Berlin wall until 1989. Before the 90's, West Berlin was a place for the alternative and autonomy movement and an important cultural place for West germany because of its status as western enclave in East Germany (the west german capital was located in the small town of Bonn at the river Rhine in this time). After the re-unification, Berlin became german capital and is now increasingly becoming the power center for Germany again, with all major media, political parties, government departments, the Reichstag (place where the german parliament (Bundestag) is located) and lots of political foundations, think-tanks and stuff like that. The negative side of this is the decrease in federalism following from the going on process of concentration of political power at one place.
And of course, a city as large and historic as Berlin is full with monuments - ranging from the Siegessäule to the Brandenburger Tor and from the modernised Reichstag building to the newly built post-modern Potsdamer Platz. Berlin is also the place where the love parade happens.