Brussels-Capital Region : Areas intended for the conservation and the regeneration of a natural environment that is of high biological value as it shelters rare animal and vegetable species or boasts considerable biological diversity

Section of the municipality's territory with a particular use of the land, as stipulated by graphical and written regulations, authorised by decree

Brussels-Capital Region : "any particularly remarquable building, including installations or decorative elements being a constitutive part of it" having been the subject of a decree for its conservation