Using a GIS the excavation plan of the Cross Roads site can be projected onto aerial photographs from the First World War. Applying this technique enables the accurate dating of trenches. The aerial photograph used here dates back to April 1917.

Furthermore it offers a convenient way to accurately date the trenches found within the excavations. The large number of contemporary photographs available for such a small area can help greatly in tracing the history and evolution of the war in its geographical (and archaeological!) context. Of course, it is also an indication of the complexity of the research, given the continuing change of structures. To apply this technique one requires vertical photographs, though other images can provide us with a great deal of important information.