Lot's to See
Berlin is a lot larger than one may think. There's so much to do there and plenty of sights to see but it is very much your big city so be prepared to walk. There is also a solemn feeling; not too much greenery only the Tiergarten; which is understood to be the feel for Berlin but it can be overwhelming a bit. There is a lot of history some of which is not so happy but never the less it is a must visit city to determine for yourself.
Insider Tip:A city pass for transit is great! If not familiar with transit maps; you can easily get lost so grab the 24-48-72 hour pass! There is a lot of restaurants especially by the museums but you can get a tastebud explosion just as great from the street vendors, there's plenty!