Having a couple of days to explore makes a world of difference, It means you can relax over meals and do things that take a little more time, without feeling frantic. You can follow this itinerary exclusively, or take some ideas from the others and mix and match to your taste. Get yourself a couple of day tickets, or explore the benefits of the 48 hour Berlin Welcome Card, which includes all of your transport plus discounts to lots of attractions and restaurants. There is lots to do and plenty of tourist options but why follow the herd when you can craft your own adventure!
1. Enjoy the Royal Quarter, Museums Island & the Upper East Side 3 hours to half day
Despite being heavily bombed during the war, Berlin did not lose all of its architectural history and a walk through Gendarmenmarkt and the Royal Quarter allows you to enjoy some of the lovely historic buildings, either in their original form or as astonishing examples of restoration after tragic events. Starting at the Brandenburg Gate, take a stroll through Pariser Platz along Unter den Linden. The idea of this may be better than the reality as there has been considerable construction along this grand boulevard for many years, however there are some lovely historic photos of the area 'Under the Linden Trees' from days gone by, that give you a sense of how it was and hopefully will be again in the future. Unter den Linden has many highlights including the atrium sculpture in the Frank Gehry designed DZ Bank Building at Pariser Platz and the statue of Lenin in the courtyard of the grandiose Russian Embassy.
Resist the temptation to turn down Friedrichstrasse for shopping and continue ahead to the area between Bebelplabtz and Schlossplatz. Here you will find palaces, memorials and cathedrals as well as the State Opera, the State Library, the German History Museum and the buildings of Humboldt University. Central to all that is of course Museum Island including the spectacular Berlin Cathedral and the huge construction project that is the Berlin Palace and the Humboldt Forum.
After you have taken in all of these grand sights, wander back through Bebelplabtz and follow the signs to Gendarmenmarkt, one of Berlin's most beautiful public squares. The grandeur of the French and German domes will impress, as will the many elegant restaurants and cafes lining the square. Some of Berlin's finest restaurants and chocolatiers can be found in this area. All that walking deserves a reward so get your credit card ready and head to Berlin's very own shopping heaven in Friedrichstrasse, where high end designers sit side by side with high street retailers.
2. Berlin by Boat 3 to 5 Hours
Water is a big feature of life in Berlin - the rivers, the canals and the lakes are all a key part of people's recreational lives. The city's waterways also happen to be a great place to experience Berlin life. There are a number of companies offering city tours by boat and if you have time, a 3 hour river and bridge tour is a wonderful way to spend an afternoon. It starts across the river from Charlottenburg Palace and travels past some of the city's greatest sites - including Museums Island, Nikolaiviertel, the historic port and the East Side Gallery. After passing under the gorgeous Oberbaumbrücke the boat makes a right turn into the Landwehrkanal and slowly glides through Kreuzberg, Tiergarten and Charlottenburg. Not only do you get to relax in the sun with on board food, drinks and ice creams, you also get to see local life in action as Berliners row past you or sit by the canal, beer in hand and offer you a friendly wave. There are longer trips available from 3 to 5 hours that include buffet lunch and extended trips out of the city into Berlin's larger connecting lakes. Tourist offices have numerous brochures and insights.
3. An evening in Kreuzberg & Neukölln 3 to 5 hours
Kreuzberg has long been considered Berlin's hippest suburb but in recent years, Neukölln has also started to develop some street credibility of its own. Given that these two suburbs sit side by side, it is very easy to explore both of them and get a taste of these diverse and interesting neighbourhoods in just one evening. If you have the good fortune of being in Berlin on a Tuesday or a Friday, you can start with a stroll through the colourful and lively Turkish market along Maybachufer. Try a few Turkish street snacks like steaming hot Gözleme (flat bread filled with spinach, cheese, potatoes) straight off the grill, or a glass of freshly pressed pomegranate juice. Enjoy the views along the canal - which runs through both suburbs - and take random turns into the local streets to see some beautiful local buildings. Make sure you look up, as Berlin's balconies are an attraction in themselves, especially in summer.
Oranienstrasse is one of Kreuzberg's most popular shopping streets and you will find some of the city's best Turkish food here - try Hasir for the true local dining experience. Or if you prefer to try some German food, Max und Moritz has a wonderful traditional ambience and great food too - try the spaetzle (a German noodle dish) or their schnitzel, which is one of the city's best. Stroll around after dinner and pop in and out of the bars - including Luzias and Roses (an exciting and bizarre gay bar with fluffy, pink walls!) or Ora, an old pharmacy converted into a very elegant cocktail bar.
Or maybe you'll start in Neukölln first and if this is the case, don't miss the the delicious Lebanese food in Sonnnenallee. Azzam is a highlight (especially the hummus) or try a shared platter at Al Andalos. After you've eaten your fill, take yourself for a walk along Weserstrasse and around Reuterstrasse. Here you'll find Berlin bar culture at its best, with people spilling out into the streets or relaxing in deep chat in lounge chairs by candle light. Try Nathanja und Heinrich in Ossastrasse or Tier in Fuldastrasse.
If you're lucky enough to get some nice weather, make sure you schedule in a take away beer at sunset at Kreuzberg's Admiralbrücke. Dozens of people gather here every evening to sit and watch the sun set over the canal. There are also two great pizza restaurants nearby and a shop to keep up the supply of cold beers.
4. Lazy neighbourhood brunch spots 2 to 3 hours
The German breakfast of bread rolls, sliced meat and cheeses, fruits and yoghurt can take some getting used to. A more diverse range of breakfasts has started to become available recently and Berlin table service being as it is, you could easily spend most of the day just eating, talking and ordering more drinks. Across the city there are plenty of great options but one of the classics is Cafe Anna Blume in Prenzlauer Berg - a florist that does an excellent spread on a Sunday for brunch and offers an impressive breakfast menu during the week too. Roamers in Neukölln offers the city's most instagrammable breakfasts (but there is often a queue) and the sun terrace at Das Edelweiss in Kreuzberg is glorious on a sunny day, to enjoy some good German specialties for brunch or lunch or even right into cocktail hour. For brunch with a view, try Käfer Dachgarten - the cafe on the roof of the Reichstag or Cafe am Neuen See in the Tiergarten for tranquil views of row boats on the lake in summer and roaring fires and all day candlelight in the winter.