Locals rarely go on sightseeing tours for tourists, which contributes to their different perception of things. For instance, living behind a wall is nothing strange when you grow up with it. When I (re)visited Berlin in 2015 for a conference, the conference excursion was a boat trip on the Spree.
While I knew that Berlin has that river, it had never become part of my perception of Berlin as a city. The Spree does nothing for Berlin like the Seine does for Paris, the Thames for London, or the Danube for Budapest or Vienna, the Rhine for Cologne (to name a few). It is small, largely canalized, and so much covered with bridges that one can easily overlook it.
These bridges connect the northern with the southern part of the city. Some of them are old, other modern. In contrast, the Spree connects the eastern with the western part, and it did so even when there was a wall. Rivers are hard to stop, like time. Crossing from west to east on this little river was a special moment for me.
Above is the cathedral, to its left the (re-)construction of the Berlin City Palace, replacing the East German Palast der Republic, that it turn had replaced the original Baroque City Palace in 1950.
Buildings serve many purposes, but they also mark and preserve time — for a while. The architects should never forget that time will flow on, inevitably.