André Godin, inspired by Charles Fourier's phalanstères, envisioned a palatial communal living space for his workers. From 1860 to 1968, the Guise Familistère, a community built for 1800 inhabitants by the great Fourierist industrialist Jean-Baptiste-André Godin (1817-1889), served as the stage for a social experiment that remained unique in its audacity, scale, and duration. The invention of a "unitary" architecture and urban planning is one of the original and pioneering aspects of the Familistère adventure. This "Social Palace" constituted a true utopia in action, which today once again arouses the interest of historians, sociologists, economists, urban planners, and architects.