In the 1920s and 1930s, the poor outskirts were reconstructed into regularly planned boroughs. Constructivist architecture flourished around that time. Housing became a government-provided amenity; many "bourgeois" apartments were so large that numerous families were assigned to what were called "communal" apartments ("kommunalkas"). By the 1930s, 68% of the population lived in such housing. In 1935 a new general plan was outlined, whereby the city should expand to the south. Constructivism was rejected in favour of a more pompous Stalinist architecture. Moving the city centre further from the border with Finland, Stalin adopted a plan to build a new city hall with a huge adjacent square at the southern end of Moskovsky Prospekt, designated as the new main street of Leningrad. After the Winter (Soviet-Finnish) war in 1939–1940, the Soviet–Finnish border moved northwards. Nevsky Prospekt with Palace Square maintained the functions and the role of a city centre.