This article explores the modernist residential complex of Aspra Spitia in Paralia Distomou, Greece, designed in the 1950s by Constantinos Doxiadis for the Pechiney aluminium company. It investigates how the settlement reflects and challenges modernist planning principles through phases of development—from its origins and forced expropriations to its vertical expansion, suburban growth, and recent transformation into a “smart city”. Combining architectural analysis with resident interviews, the study examines tensions between modernity, class stratification, and heritage preservation. Aspra Spitia emerges as both a legacy of industrial modernism and a living site of spatial, social, and technological negotiation.