Anyone whose image of Berlin derives from war films or spy stories is in for a pleasant surprise. Away from the busy industrial and commercial centres of western Germany, this still ever so slightly schizoid city has long been a bohemian bolthole and a refuge for the unconventional. The combination of top-flight museums, galleries and concert halls with a thriving offbeat underground in art and music mark Berlin as a major cultural centre.

An orderly sprawl with no solid centre, Berlin’s twin hearts were beating around Bahnhof Zoo in the west and Friedrichstrasse in the east long before four decades of Cold War division redrew the distinction in concrete and barbed wire. Today’s unified capital and city-state is still divided by the Mauer im Kopf, the Wall in people’s heads that keeps west and east Berliners wary of each other. But it’s also two cities in seasonal terms, and summer Berlin takes some beating.

If you're going in spring or summer don’t miss such events as the Karneval der Kulturen (www.karneval-berlin.de) in late May, Christopher Street Day Parade (www.csd-berlin.de) in late June or Love Parade (www.loveparade.de) in mid July, when the streets of this party town throng with revellers celebrating to a soundtrack of world music, house or techno. And when it’s finally time for a break from the restless nightlife or the shameless gay scene, the fringes of this thoroughly modern metropolis - accessible via an efficient public transport system – provide forests, swimming, boating lakes and even a sandy bathing beach or two.

Most unmissable Berlin sights are in and around central Mitte. The east-west axis of Unter den Linden is as good a place to start as any. Frequent Nos.100 and 200 buses run the length of the tree-flanked boulevard, linking it with Bahnhof Zoo in the west. Its western end is marked by the iconic Brandenburg Gate, once closed off between East and West Berlin, which gives on to the huge Tiergarten park. North-west of the Gate is the new government quarter and the revamped Reichstag, crowned by Sir Norman Foster’s magnificent glass cupola (Platz der Republik, +493022732152, www.bundestag.de). A walk to the top is especially appealing at sunset.

South of Unter den Linden is the pleasant Gendarmenmarkt square, topped and tailed by the German Cathedral (Deutscher Dom, +493022730431) and the French Cathedral (Franzosischer Dom, +49302291760). At the eastern end of Unter den Linden is Museum Island (Museuminsel) where a clutch of superb collections include the Pergamon-Museum (+493020905577, www.smb.spk-berlin. de) with the Babylonian Gate of Ishtar. The majestically porticoed Altes Museum and the 19th-century art at the Alte Nationalgalerie (209 050, www.smb.spk-berlin.de) are also worthwhile. The other landmark is the bombastic Berliner Dom (+493020269133, www.berliner-dom.de).

Eastwards is the unearthly concrete expanse of Alexanderplatz and the landmark ball-and-spike TV Tower (Fernsehturm, +49302423333, www.berlinerfernsehturm.de), with its revolving observation deck. South is the reconstructed medieval Nikolaiviertel and remnants of the original medieval wall.

North of Alexanderplatz, the renovated Scheunenviertel (‘Barn Quarter’) is packed with galleries, bars and shops. Its focal point is the Hackesche Höfe, a warren of courtyards typical of the German art nouveau style.

Nearby Auguststrasse is the art scene’s main drag, while the revived Jewish Quarter centres on the Neue Synagoge (New Synagogue, Oranienburger Strasse 28-30, +493088028451, www.cjudaicum.de).

Prenzlauer Berg has gentrified rapidly and, though containing few specific sights, is one of the most relaxed areas for a meal or a drink. Friedrichshain has a more hardcore communist feel. The lively, youthful nightlife scene around Simon-Dach-Strasse and Muhlenstrasse contrasts with the eerily wide main drag, Karl-Marx-Allee, a treat for fans of Soviet-style Stalinist architecture.

Once the heart of nonconformist Berlin, Kreuzberg has lost its monopoly on artiness and anarchy but remains fascinatingly diverse.

Its northern part has a number of excellent museums such as the Deutsches Technikmuseum Berlin (Trebbiner Strasse 9, +4930902540, www.dtmb.de) and the Cold War exhibit at the Haus am Checkpoint Charlie (Friedrichstrasse 43-45, +49302537250, www.mauer-museum.com).

No one should miss the Jewish Museum (Lindenstrasse 9-14, +493025993300, www.jmberlin.de) where the exhibition is almost upstaged by Daniel Libeskind’s remarkable deconstructivist architecture.

Neighbouring Schöneberg is largely residential but offers great bars in its northern reaches, also the hub of Berlin’s gay scene.

Tiergarten is dominated by the huge park of the same name. Along its southern fringe are a number of excellent museums, the best being the traditional Gemaldegalerie (Matthaikirchplatz 8, +49302662951, www.smb.spk-berlin. de/gg), the more contemporary, Mies Van der Rohe-designed Neue Nationalgalerie (Potsdamer Strasse 50, +49302662651, www.smpk.de/nng) and the Filmmuseum Berlin (Potsdamer Strasse 2, +49303009030). This lies within the huge complex of modern buildings at Potsdamer Platz, a former no man’s land now intended as the city’s unifying commercial centrepiece. Opinions differ as to the success of the architecture around here, despite names such as IM Pei, Helmut Jahn, Richard Rogers and Renzo Piano. At the opposite, south-west corner of Tiergarten is Berlin’s beautifully landscaped Zoo&Aquarium (Hardenbergplatz 8, +4930254010).

To the south-west lie the Dahlem museum complex, the vast Grunewald woods and the assorted watery pleasures of the Wannsee and assorted smaller lakes – Strandbad Wannsee is Europe’s largest inland beach. Heading south-east, you can drink in the villagey charms of Köpenick or the products of the Berliner Burgerbräu brewery at Friedrichshagen, which throws open its gates for an annual summer celebration. Boat trips can be had on the nearby Muggelsee.