Add to ORKGInternational audienceThis exploratory paper aims at showing how the fractal dimension can be used to characterise the spatial structure of built-up areas within the periurban fringe. The southern periphery of Brussels is considered here. Two estimation techniques (correlation and dilation) are applied to surface areas, and one (correlation after dilation) to the borders of built-up areas. They are applied to windows of fixed size. Fractal dimensions are then compared with traditional socio-economic and morphological indicators. The results are interpreted in the context of urban sprawl and polycentric development of the peripheries. These analyses confirm the usefulness of the fractal approach for describing built-up morphology.Cet article...