Multi-storey housing estates are built according to contemporary ideas on town planning.
Buildings become simple and functional.
An economic depression and the second world war hit Europe
A rapid movement of people from rural areas to cities is triggered by technological advance.
Less land must be used for building
Parts of cities become slums.
A number of these have been knocked down.
Modernist ideas cannot be put into practice until the second half of the 20th century
All decoration is removed
Light steel frames and lifts are developed.
