 A leader in the design of social housing was Hilding Ekelund – who had previously been responsible for the design of the athletes' village for the Olympic Games.A challenge to the traditional urbanisation process came, however, with the design of "forest towns", high-rise developments set in forested areas on the outskirts of the major cities, such as the Pihlajamäki suburb of Helsinki (1959–1965), based on a town plan by Olli Kivinen, and building designs by Lauri Silvennoinen, the area comprising white Functionalist-style 9-storey tower blocks and up to 250-metre-long 4–5-storey "lamella" blocks dispersed within a forest setting.Pihlajamäki was also one of the first precast concrete construction projects in Finland.