An analysis of declassified satellite images from the Cold War era has revealed the remains of 396 previously unknown Roman forts in the Middle East.
A team of researchers at the University of Dartmouth have used declassified Cold War satellite imagery to show the placements of a line of Roman forts built 2,000 years ago. Their locations span from Mosul in Iraq all the way to Aleppo in Syria.
In doing so, the team refuted the findings of Father Antoine Poidebard. In the 1920s he conducted one of the world’s first aerial surveys of the area using a WWI-era biplane. Poidebard documented 116 forts, arguing that they were constructed from north to south to establish an eastern boundary of the Roman Empire.
“I was surprised to find that there were so many forts and that they were distributed in this way because the conventional wisdom was that these forts formed the border between Rome and its enemies in the east, Persia or Arab armies,” said lead author Jesse Casana. “While there’s been a lot of historical debate about this, it had been mostly assumed that this distribution was real, and that Poidebard’s map showed that the forts were demarcating the border and served to prevent movement across it in some way.”
Above, forts documented by Father Antoine Poidebard in 1934, compared to, below, those found on satellite imagery / J Casana et al
The team based its findings on declassified Cold-War era CORONA and HEXAGON satellite imagery collected between 1960 and 1986, made accessible through the open-access CORONA Atlas Project. However, Casana and his colleagues developed better methods for correcting the data and made it available online.
The researchers examined satellite imagery of approximately 300,000 square kilometres (115,831 square miles) of the northern Fertile Cresent. The team mapped 4,500 known sites and then systematically documented every other site-like feature in each of the nearly five by five kilometre (3.1 mile by 3.1 mile) survey grids.
Using this technique, the team added 10,000 undiscovered sites to its database.
The team focused on identifying forts that matched Poidebard’s descriptions. These were distinctive square structures measuring approximately 50 by 100 metres (0.03 by 0.06 miles) – large enough to accommodate soldiers, horses and camels. They were made of stone or mud-brick and often included lookout towers in the corners or sides.
Out of the 116 forts documented by Poidebard, the team was able to locate 38, despite the damage inflicted by agriculture and land use. In addition, the researchers also uncovered 396 previously unknown sites, some of which were built around a mounded citadel.
Of the newly found forts, 290 were located in the study region and 106 were found in Jazireh, located in Syria.
“Our observations are pretty exciting and are just a fraction of what probably existed in the past,” says Casana. “But our analysis further supports that forts were likely used to support the movement of troops, supplies and trade goods across the region.”
The researchers’ findings were published in the journal Antiquity.
