Berlin is the capital of Germany. Because of its history of urbanization, Berlin possesses a polycentric urban structure. In the nineteenth century, the city emerged as a European prototype of effective urban administration and municipal self‐government. From large Wilhelminian tenements to world heritage sites of the early communal housing estates to the modernist buildings of the postwar period in the West and the socialist housing estates in the East, Berlin's history is still present in the built environment. After the fall of the Berlin Wall in 1989 and the city's reunification, Berlin had to undergo a comprehensive transformation of its urban structure.