The remains of Charax Spasinou are spread over five square kilometres. Mapping is the essential precursor to any archaeological excavation, but exploring such a large site poses particular problems. Our solution was to trial photogrammetry using a small aerial drone.

A digital model of part of the city walls of Charax Spasinou

Flying in a grid pattern controlled by the on-board gps, the drone takes a series of overlapping vertical images of a given part of the city. These are compiled into a mosaic and then turned into a digital model by specialist software.  By this means we will be able in time to create an elevation model of the entire city.Drone photography can map the modern-day surface of Charax Spasinou, but we also needed to find out what was left under the ground. For that we undertook a magnetometer survey of a small section of the city.

City blocks revealed by magnetometry

The results were astounding: entire city blocks were revealed, densely packed with buildings. The regular grid is a feature of Hellenistic towns, so here we have the preserved original lay-out of Alexander’s city! To the south, an old river bed was revealed, which cut into the remains of the city, a reminder of the ever-present danger of flooding that the city faced.

We checked the results of the magnetometer survey through selective excavation, confirming that substantial buildings are still present. Our work at Charax Spasinou is in its infancy, but these preliminary results show the enormous potential of the site. The kingdom of Characene is about to emerge from the shadows.