Romans did not add anything to Greeks’ general and theoretical basis, like globe’s shape and dimensions, distributions of land and water, ways to represent a spherical shape on a flat surface, but their importance is based on the geo-cartographic knowledge aimed at practical requirements of the military, commercial and administrative activities.
In this field the most important evidence is given by large-scale cartography of the Empire, the Orbis Pictus, realized during Augustus reign, in which the essential elements consisted in routes, distances,administrative borders, peculiarities of the places along the paths.
This document and its tabulae, mostly used  by army and government officials, were the source for the creation of two different instruments (for a practical use) destined to a large diffusion: “itineraria scripta”, a collection of locations with information on the various distances among them, peculiarities of the routes, position of the resting points and the “itineraria picta”, real street maps that were drawn.

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