A newly released map and digital dataset called Itiner-e expands the known length of the Roman Empire’s road network by over 110,000 km.
Itiner-e is the most intricate and comprehensive open digital dataset of roads throughout the Roman Empire. Image credit: de Soto et al., doi: 10.1038/s41597-025-06140-z.
During its peak in the second century AD, the Roman Empire boasted a population exceeding 55 million and extended from present-day Britain to Egypt and Syria.
While the extensive road network facilitated development and maintenance, maps remain incomplete, and existing digitized versions are of low resolution.
“The study of Roman roads has a long-standing history,” remarked Tom Brumans, a researcher at Aarhus University, along with his colleagues.
“A plethora of information about roads has been confirmed through archaeological excavations, surveys, milestones placed regularly along Roman routes, and historical texts like the Antoninian Itinerary and the Poitingeriana Table, which offer a detailed regional overview of key connections between settlements and Roman roads.”
“However, the pursuit of identifying and locating this diverse body of research is complicated by a lack of comprehensive integration and digitization across the empire.”
Researchers employed archaeological and historical records, topographic maps, and satellite imagery to compile the Itiner-e dataset.
This dataset includes 299,171 km of roads, covering an area of approximately 4 million km, a marked increase from the prior estimate of 188,555 km.2.
The growth in road coverage is attributed to enhanced documentation in the Iberian Peninsula, Greece, and North Africa, as well as adjustments to existing road routes based on geographical realities.
This includes the provision for roads traversing mountains to follow winding paths, rather than straight lines.
Itiner-e encompasses 14,769 road segments, with 103,478 km (34.6%) classified as primary roads and 195,693 km (65.4%) as secondary roads.
Only 2.7% of the road locations are known with certainty, while 89.8% remain less precise, and 7.4% are based on hypotheses.
“Itiner-e is the most detailed and comprehensive open-access digitization of Roman roads, and it also highlights existing knowledge gaps in the road system,” the authors stated.
“They emphasize that Itiner-e does not reflect temporal changes in the road network, and further studies are necessary to explore this across the Roman Empire.”
“Itiner-e could serve as a valuable resource for future research on the impact of Roman roads on connectivity, governance, migration, and disease transmission within the empire.”
For maps and datasets, refer to the paper published in Scientific Data.
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P. De Soto et al. 2025. Itiner-e: A high-resolution dataset of roads in the Roman Empire. Scientific Data December 1731. doi: 10.1038/s41597-025-06140-z
Source: www.sci.news
