Berlin is big and it is a surprisingly green city. You find a few canals like this one, the river Spree, the vast Zoo right where a center would be expected, and you also find that almost 30 years after the unification, the wounds of the war are still visible.
It’s not decay, not at all. It’s the shape of the city itself. It’s what you get when you divide a big city in two for 44 years. Different ideas of architecture have prevailed in the two cultures, east and west, and the very center has been a dead border area. We’ll see a lot of that soon.