Pre-Bonifica maps of the Agro Pontino: an assessment

The morphology of the Agro Pontino (Latina, Italy) has been greatly modified by the fascist reclamation (Bonifica), in particular by the subsequent soil subsidence due to the drainage of its peaty lowlands and by massive dredging and land raising. Obviously, this constitutes a strong bias for reconstructing the ancient landscapes. However, pre-reclamation maps can be used to address the problem. In particular, the 1930s maps made by the Italian Military Geographical Institute are of exceptional importance for both the reconstruction of prehistoric and historic landscape, and for detecting the more recent, human-induced changes in its morphology. Unfortunately, the datum of the maps is unknown. In this paper we try to estimate a standard Molodensky transformation to convert the map to the current projections, by surveying points which are unambiguously identifiable both in the terrain and on the maps.