Germany's urban hierarchy is led by Berlin—then a tight cluster of four metros.
German cities have tight administrative boundaries. Rhine-Ruhr (10M+) and Rhine-Main (5.8M) are polycentric megaregions—city-proper populations understate economic weight.
Stuttgart (630K), Düsseldorf (620K), Dortmund (590K), Essen (580K), Leipzig (600K), Bremen (570K), Dresden (560K), Hannover (540K), Nuremberg (520K).
Berlin growing (+40K/yr); Munich, Hamburg steady; Rhine-Ruhr cities stable/slight decline. Leipzig, Dresden growing (post-reunification revival). Suburbanization + immigration drive metro growth > city growth.