Byzantium, today’s Istanbul, was the true hub of continental trade and transit in the Roman Empire, a structural analysis of 300,000 kilometres of ancient roads has shown.

The study, entitled “Network science reveals the structure and lasting impact of the Roman road system”, was published on September 15 by Nature.

In 20 BC, Emperor Augustus erected the Milliarium Aureum (The Golden Milestone) in the Roman Forum to signify the ultimate point of origin of the ancient world’s most ambitious transport network. For two millennia, the adage "All roads lead to Rome" stood as an unchallenged truth in historical geopolitics and infrastructure planning.

However, a comprehensive study led by classical archaeologists at Denmark’s Aarhus University and the Autonomous University of Barcelona, suggests that history's most famous logistics hub was misplaced.

The empire’s operational centre of gravity actually lay not on the banks of the Tiber but on the shores of the Bosporus. Byzantium, known from late antiquity as Constantinople, was structurally far more central to continent-wide transit than Rome ever was.

Rome on the periphery

While Rome functioned as an effective maritime terminal on Italy's Tyrrhenian coast, it sat on the periphery of the broader multi-continental overland grid. Within Italy itself, structural modelling revealed that the peninsula’s most heavily trafficked artery ran along the opposite Adriatic coastline, bypassing the capital entirely.

The network prioritised efficiency at the regional level. Provincial capitals such as Ankara (Turkey), Corinth (Greece) and London (Britain) exhibited exceptionally high local network centrality. This layout allowed the imperial administration to optimise local commerce, military dispatch and revenue collection long before goods or taxes were remitted toward the capital.

Where continents meet

Situated directly at the nexus where Europe meets Asia, Constantinople served as an indispensable bottleneck for transcontinental trade. Ferry crossings across the Bosporus bridged European and Asian road corridors, turning the new capital into the hyper-connected node that Rome had symbolically claimed to be.

The longevity of these trade corridors represents one of the most enduring capital investments in human history. Following the fall of the Western Roman Empire in 476 AD and the Eastern Empire (Byzantine) in 1453, the underlying grid continued to anchor European and Near Eastern transit.

These roads in many places served as the main communications throughout the medieval period until the development of railroads in the 19th century and highways in the 20th century.

In numerous regions, contemporary transport links directly inherit Roman blueprints. Spain's modern N-340 motorway, for instance, stretching from Cadiz toward the Pyrenees, directly overlays the ancient Via Augusta, passing beneath the Roman Arc de Bera, the triumphal arch in proximity to Tarragona.