What Berlin got right is that they tried to get all of society into the same building. As in the well-off into the 1st floor (Belle Etage) the poor under the ro

What Berlin got right is that they tried to get all of society into the same building. As in the well-off into the 1st floor (Belle Etage) the poor under the roof, but the idea was to have the doctor living in the same building as the plumber. I think that idea is key to having livable cities. Of course a lotbof happened between these ideas and the situation now. Heidelberg is of course pittoresque but not a city in the same league in size. Maybe Mannheim could be taken as a town planning model.