Mobility in ancient times: Combining land and water costs

Abstract

Abstract Mobility in Roman Times can be modelled using GIS tools. These resources allow us to understand how communications could be done. In this paper, we debate about a better way to use these models in cases where we have a navigable river in our studied territory. Normally these water spaces are considered as limiters of land movement, because of the real nature of Least Cost Path tools, that will always consider them as natural paths. We argue that in roman mentality the rivers are the best areas for movement and in our current development we could not integrate them with land ones. The main problem is the principal factor in river mobility, the current upstream and downstream. We present a tool in ArcGIS to calculate the Horizontal Factor of the river s current. This allows us to test the integration and results of a combined land and river analysis in different scenarios, like the connexion between centre and node, like a city to the villa. Finally, we argue about the need of this kind of integration to better understand mobility with the ancient mentality, allowing us to consider other ways of cost, not only in terms of time but also in the increased cost value of product transportation.