Berlin
Berlin is history's open workshop: nowhere else can you walk from an emperor's island of museums, past the parliament's glass dome, along the line where a wall cut a city in two, and end at a techno club in a former power station — all before the currywurst stand closes, which it doesn't. The city is poor in polish and rich in space, and it guards that trade fiercely.
The sensible traveller gives the Museum Island a morning and Pergamon-scale patience; walks the Wall's double-brick line through the Brandenburg Gate to the Holocaust memorial's silent grid; and crosses the Spree into Kreuzberg for Turkish markets, canal banks and dinner that starts when it starts. Sunday belongs to Mauerpark's karaoke and flea chaos — Berlin at its most Berlin.
The Guide's honesty: the famous clubs choose at the door and explaining why would ruin it — dress dark, go late, have no plan B in your face —; cash still rules more counters than any capital this side of the millennium; and the history is not curated for comfort: the memorials ask you to feel bad accurately. Let them.