Using a GIS, a map was generated which indicated the altitude of the region where the A19 extension is planned. The map doesn’t indicate significant differences in altitude, but the strategic advantage of only a few metres was known to be potentially life saving. The German troops around Ypres took the higher ground, which enabled them to have a far better view of the battleground.

These collected and analysed data were used as a guide for the subsequent field-walking campaign (total length of 7 km and 100m wide).

The results of the field walking campaign were processed in a G.I.S. database and all collected finds were closely studied. The concentrations on the surface were compared with the first maps already compiled using literary sources, photographs and trench maps. The different sources showed clear convergences.