Few cities have seen as many changes over recent years as Berlin. The two separate entities that existed before the Wall came down have become one again. There's hardly a trace left of the former east-west division. The new architecture on Potsdamer Platz and in the government quarter forms a fascinating contrast to the late 19th century buildings of Charlottenburg. One minute you're on an elegant boulevard, the next you’re in one of the city's more alternative neighbourhoods. But the city is not only renowned for its architectural monuments; it also has museums, green oases and nightlife galore.