Aerial Reconnaissance in Archaeology - from Archives to Digital Photogrammetry

Most human interactions with the landscape have left and continue leaving traces around us in different forms. Field bounda-ries, land divisions, monumental buildings and communication systems or water management infrastructures characterize our sur-roundings in a constantly changing multi-stratified environment. Whatever photograph we take, it captures a single moment, a specifictime or it freezes a unique memory. If we look back to that photograph after some time, we are probably going to recognize the place wevisited, the history of the monument in the background but also the renewed house close by. Aerial photographs do the same, just froma different perspective. It has been said that 'there is every possibility that a single aerial image will record information that spans time from the fraction of a second it was taken to millennia in the past' (Cowley and Palmer 2009:129). And the job of the photo-interpreteris to 'read' as many details as possible of that frame and to try and reconstruct a history behind it, making sense of images by con- stantly isolating and merging time phases, relative and (ideally) absolute chronology of the depicted objects as for a non-destructivearchaeological excavation. Dating is not an easy task and it is usually strictly linked with the self-training and experience of the air- photo-interpreter (API for short). New technologies, sensors and software are today supporting and largely helping the interpretative process; this paper pinpoints some of the most important steps to achieve a possible understanding of the area under investigation, presenting an ideal bridge that spans from historical archives to digital photogrammetry