Starting from Berlin: Getting around
Berlin has a superb public transport system, and this is definitely the best way to get around. Buses, local trains, trams and underground are all integrated into one network where you can use the same ticket.
There is an excellent section on the city website, which shows routes and explains in English how the ticketing system works.
Many visitors buy the Berlin WelcomeCard, which entitles you to free use public transport in the city centre, reduced entrance into many tourist attractions and special offers in a range of restaurants and shops.