There are also a number of brilliant walking tours (if you are able to walk a fair distance would highly recommend this rather than a bus tour) from original berlin walks - all the guides are fantastic and the tours are really cheap!
Don't go to Berlin without a trip to Potsdam (you will need an extension to the zones on your travel cards for this unless you buy one covering all zones) - it's fabulous, reminded me of a model town, full of beautiful palaces and a lovely day out. If you do want to see the sights without walking the number 100 or 200 stops at all the major sights and using these is far cheaper than paying for a pricey tourist bus!
Wansee was also fabulous if you fancied a chilled day - even got a beach! If you want to visit the dome on the Reichstag you should go for opening time (about 8am) or just before it closes (try 8.30 - 9pm) to avoid spending hours queuing - it's free and the views are amazing (there is loads of free info available once you are there) so it's worth doing this rather than paying to see the same thing from the TV Tower on Alexander Platz.
Also have a look in the DZ Bank on Pariser Platz to see the interior - building looks plain outside but inside is a huge fish like sculputre (you can see the roof from top of Reichstag) by Frank O Gehry which is well worth a look (remember its a working bank though).
The old palace of the crown princesses next to the state opera has various home made cakes everyday from 12 - do not leave without trying one (the marzipan cake is fab!). Quite pricey but worth it for the lovely interiors and if its a nice day you can sit on the terrace outside overlooking Babel Platz.
The Museum Island is well worth a visit - all the buildings are stunning inside and the Bode Museum has the most amazing collection ever - go on Thursdays as they are open late and get a day ticket allowing you to visit all the museums (much more economical than paying individually).
There is loads of free stuff to do in Berlin - try the Topography of Terror, an open air museum about the 3rd reich and war. Theres a big bookstore on Unter den Linden (can't recall the name) that shows films of berlin and has all sorts of info on the history of the city. There is also a museum dedicated to K F Schinkel who was a major architect in Berlin - its in an old church just behind the Opera and has beutiful windows and is full of sculptures.
The zoo is a nice day out too - don't miss Knut the Polar Bear!
Travelling to the airports is easy by Public transport too - bus 109 goes to tegel airport from the zoo station and there are loads of trains to/from Schonefeld airport to stations across berlin. I got a taxi from the airport and it was about 35 euros to west berlin, the trains was about 3 euros and from the zoo there was a bus to the front door of my hotel - used the public transport to go back!!
If you are going to Germany do not miss Berlin - its the absolute best place ever in the whole world!!
Suzanne Armstrong
November 2008