How Many Denarii From Roma to Londinium By Ox Cart in January?

Spanning three continents and a quarter of the human population, the Roman Empire created an extensive transportation and communication network that relied on human, animal and ship travel. Conventional maps that represent this world fail to capture the actual travel conditions that determined the flows of people, goods and information.

This interactive model created at Stanford University calculates the time (in days) and expenses (in denarii) for travel by various modes (foot, pack animal, ship, and caravan) between major cities in the Roman Empire. By simulating movement along principal Roman roads, navigable rivers, and sea routes, it reconstructs the duration and financial cost of travel in antiquity.

The model includes 1,371 total base segments. It allows users to generate time and expense simulations for connections between any two sites across different media and for specific means and mode of transport and months of the year. It considers fourteen different road travel modes that generate nine discrete outcomes in terms of speed and three in terms of expense for each road segment. Road travel is subject to restrictions of movement across mountainous terrain in the winter and travel speed is adjusted for substantial grade.

The model's maritime network consists of 900 sea routes (linking 450 pairs of sites in both directions), many of them documented in historical sources and supplemented by coastal short-range connections between all ports and a few mid-range routes that fill gaps in ancient coverage. It also includes two types of river boat. River travel speed is determined by ancient and comparative data and information on the strength of river currents. Cost simulations are sensitive to the added cost imposed by movement upriver and, where appropriate, take account of local variation in current and the impact of wind.

ORBIS help reveal the true shape of the Roman world and provides a unique resource for understanding premodern history.

Thanks to Todd Litman