Brussels-Capital Region: The geotechnical maps of Brussels were elaborated by J.P. Dam, under the direction of prof. J. Nuyens, V. Roisin and R. Thonnard of the Université Libre de Bruxelles (ULB) and of the Vrije Universiteit Brussel (VUB), members of the Centre Interuniversitaire pour la Cartographie Géotechnique directed by J. Nuyens (ULB). They were then published at a scale of 1/5000 between 1976 and 1990 by the ‘Institut Géotechnique de l’Etat’ (State Geotechnical Institute). The constituent documents (maps and associated reports) provide an overview of the following points: - tests carried out in the region ; - depth of the water table ; - nature and position of the tertiary substratum ; - nature and strength of the various surface layers; - units with a specific overlay of the formations encountered. Their initial objective was to respond to the needs of the builders for synthetic and easily accessible documentation relating to the subsoil of the Brussels region. The plates and documents provided did not claim absolute precision because of the interpolations and extrapolations necessary for their establishment. The present archive is presented in three forms: - Digitized maps and associated FR/NL explanatory notes .pdf ; - Georeferenced 'raster' maps (lambert 72); - Vector' maps (lambert 72). List of available maps: 31.2.4; 31.2.6; 31.2.8; 31.3.1; 31.3.2; 31.3.3; 31.3.4; 31.3.5; 31.3.6; 31.3.7; 31.3.8; 31.4.7; 31.7.1; 31.7.2; 31.7.3.