Documenting Archaeological Sites on Mountains and Slopes with Drones

The addition of drones to the archaeologist's toolbox has brought about exciting new possibilities, particularly for field research and the conservation and protection of our built heritage. As drones become more widely available and effective, the challenge of precision becomes more important. Better georeferencing and higher-resolution outputs are the current thresholds. In order to achieve the second objective with our current equipment, drones have to fly closer to the ground and, ideally, follow the elevation of the surface. This task can be extremely complicated along the steep surfaces and mountains typical to the Andean region where we work. In this article, we present a recording (flying and photographing) methodology that achieves a higher ground resolution by dividing up the sites into several altitudinal sections, which are flown independently yet processed photogrammetrically as a single set. We have named this methodology “Flying Slopes in Multiple Stepped Polygons.”