Satellite images rewrite history of Rome’s eastern border
Utilizing declassified images from the CORONA and HEXAGON spy satellite programs, a team of archaeologists identified nearly 400 Roman fortresses throughout the northern Fertile Crescent. Publishing their findings in the journal Antiquity, the team suggests that the extensive distribution of these fortresses may rewrite our understanding of their purpose.
The team from Dartmouth College identified the Roman fortresses while carrying out an extensive remote sensing survey, covering over 115,000 square miles from western Syria to northern Iraq. The survey located more than 10,000 potential archaeological sites, including 396 Roman fortresses.
The fortresses are easily identified by their standardized square shape, typically 160 to 260 feet long per side, although a few are as large as 650 feet per side. The smaller fortresses are often isolated architectural features, far from settlements and in marginal regions. The larger fortresses, however, include additional features and more extensive fortifications. These larger fortresses were often located closer to settled and agricultural areas. Although ground surveys and excavations have only been carried out on a handful of these fortresses, most appear to have been used between the second and sixth centuries CE.
An early aerial survey of the region in the 1930s by the French priest Antoine Poidebard identified 116 Roman forts in a roughly north-south line that followed the military road of the emperor Diocletian (r. 284–305 CE). Poidebard, and many scholars since, have assumed that these fortresses were constructed along the empire’s eastern border as a way of defending against Arab nomads or Persian armies. Yet, a major problem with this theory was the spacing of the fortresses, which were too spread out to form an effective barrier.
However, the Dartmouth team’s discovery supplies evidence for a new understanding of these fortresses. Looking at a far wider swath of the region, they identified not a north-south line, but an east-west pattern. This conglomeration of fortresses extends from Mosul, through Nineveh, the Khabur and Balikh valleys, the plains west of the Euphrates, and to western Syria. Many of these fortresses were in marginal areas with sparse habitation, regions that would have been far behind the empire’s eastern border. Based on this evidence, the team believes the fortresses instead operated as waystations, supporting the movement of troops, supplies, and trade.
According to the team, we can “view the forts of the Syrian steppe as enabling safe and secure transit across the landscape, offering water to camels and livestock, and providing a place for weary travelers to eat, drink and sleep, thereby playing a critical role in bringing east and west together.”
Sign up to receive our email newsletter and never miss an update.