The lower Tiber (Central Italy) is one of the best studied and most densely occupied landscapes of Europe, forming a resource which has recently been enhanced by Tiber Valley Leverhulme project of the British School at Rome, an institution which will continue to provide important management and logistical support. The missing key element from the current GIS is a sufficiently precise DEM to tackle scientific problems of land management and erosion over the last 4,000 years. The project has selected four sample areas related to the 50 x 50 km core region to provide 1) a detailed DEM for a key area of dissected volcanic landscape (employing LiDAR) (Nepi - Civita Castellana zone) 2) comparative ground truthed microtopographic and geomorphological data from the Tiber delta to provide a measure of LiDAR accuracy under different conditions, 3) a regional analysis of ancient drainage tunnels in comparison with drainage patterns modelled from the accurate DEM (Veii zone), 4) multi-spectral data to assess the completeness and survival of the sample of over 5,200 archaeological sites from Tiber catchment. The results will form a platform for modelling and ground truthing (through coring, trenching and radar) erosional processes.