In the 1930s modernism characterized the development of the city as it grew. New residential areas sprang up such as the development on Gärdet while industrial development added to the growth, such as the KF manufacturing industries on Kvarnholmen located in the Nacka Municipality. In the 1950s, suburban development entered a new phase with the introduction of the Stockholm metro. The modernist developments of Vällingby and Farsta were internationally praised. In the 1960s this suburban development continued but with the aesthetic of the times, the industrialized and mass-produced blocks of flats received a large amount of criticism.