Kreuzberg.

Kreuzberg, just south of the city center, is one of Berlin's oldest districts — but when the Wall went up in 1961, it got pushed out to the edge, cut off from the old heart of the city. That isolation turned it into the playground of Berlin's alternative scene and a center of Turkish immigration. Failed urban planning fed a major squatting movement in the early 1980s, and a tradition of political activism that sometimes spilled into street riots.

Today Kreuzberg is reconnected to the city center and transforming again, now the main place to go out in Berlin, packed with cafés, bars and clubs. Its walls are covered in graffiti and political slogans, its streets full of punks, Turks, hipsters and partygoers.

This is Germany's alternative headquarters — some of the city's most beautiful corners sit right next to its most run-down, and it's essential if you want to get past the usual tourist spots. We start at Kottbusser Tor, see Oranienplatz, the Bethanien art center and the treehouse by the old Berlin Wall, and explore the Wrangelkiez and the elevated U1 line, among other places.