In the light of the division of land, and more precisely of the large landed property, this research proposes an original and descriptive look at the urbanisation of Walloon Brabant and takes place in a corpus of studies in urbanism in Belgium. In particular, it focuses on the large landed properties transformations in Walloon Brabant and their impact on the building up of urbanised territories, within the metropolization processes at work around Brussels during the 20th century. Based on a morphological description of the large landed estates transformations, this work examines their influence on the contemporary form of the urbanised territory. The investigation is carried out in the territory of Walloon Brabant, historically composed of large landed properties that belonged to the nobility, the Church or to industrial and bourgeois landlords. The following question arises: what forms of urbanisation did the large estates in Walloon Brabant produce and how does this affect current urban conditions? The reading of the construction of the material conditions of urbanisation in Walloon Brabant during the 20th century I propose is done through the investigation of six case studies and the creation of cartographic representations. I analyse the large parcel structures to determine whether the large estates played a constitutive role in the production and transformation of the spatial and material conditions of urbanisation within the metropolization processes. Six case studies depicting a variety of situations unfold specific spatial configurations of Walloon Brabant: housing estates, business centres, industrial zones, parks and open spaces, ponds and forests, golf courses, etc. The studied situations highlight the types of urbanisation produced after the dismantling or the permanence of certain large landholdings. My thesis is that the evolution of urban conditions in Walloon Brabant has been influenced by the transformations of the large estates and constitutes today a specific urban, metropolitan and landscaped ...