An extensive network of dozens of Roman army camps was discovered in a mountainous region of northern Spain.
The camps show the size of the Roman army about 2,000 years ago during the conquest of the Iberian Peninsula.
“It reveals the intense Roman activity at the entrance to the Cantabrian Mountains during the final stage of the Roman conquest of Spain,” said study co-author João Fonte, landscape archaeologist at the University of Exeter in England. He said in a statement.
The remains of the 66 camps, designed for training and shelter, have been discovered using remote sensing technology. They range from small forts of a few thousand square feet to large fortified enclosures of 37 acres (15 ha) and help explain how the Romans succeeded in their 200-year-long battle to conquer the Iberian Peninsula from the indigenous population.
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The large number of soldiers staying in these camps led to attacking the local population from different directions.
Fonte said that the Romanian army set up these temporary settlements when “moving through hostile territory or when carrying out maneuvers around their permanent bases.” They were strategically placed to help soldiers get out of the cold winter months without leaving their posts.
“We have identified many locations because we used different types of remote sensing,” Fonte said. The team analyzed aerial photography and satellite imagery, including Google Earth, creating 3D models of the terrain and using drones to make detailed maps of the area.
Most of the sites are found near where the Romans later established important towns.
The results are detailed Dec.2 in the journal geology.
Originally published on Live Science.