Aerial survey over the plain of Caen has revealed a substantial number of ditched enclosures which can be attributecd to proto-historical groups. This type of ground occupation can now be confirmed on an equal basis with other regions of northern France. Photographical evidence thus constitutes a first-hand source of information for the study of pre-roman territories. The approach to ground occupation of the downstream Seulles basin is conducted on two scales : the first covers the whole of the selected area with thirty-three communes. All the archaeological structures spotted on the aerial photographs (ditched enclosures, pits, gallo-roman substructures) are related to the corresponding XIX th century land register. The IGN (National Geographical Institute) maps based on the hydrographic systems are used to list pro-tohistorical and gallo-roman settlements in the communication network which existed before land real-locations. Ancient names studied through a few manuscript sources, mediaeval and moderne, are reinstated on the ground within archaeological areas. A central commune, in the basin, is selected as head-quarters for various explorations. Several enclosure systems, typical of those discovered in the plain of Caen, appear to organically belong to the land. Probing is carried out to suggest a possible type-chronology. Systematic ground prospecting reveals the archaeological environment. The summing-up of result 
allows rural occupation schemes to be out lined.