The Itinerarium Provinciarum Antonini Augusti is a collection of some 225 routes along the roads of the Roman Empire. In each case the beginning and the end of the route are given, together with the total mileage, and there then follows a list of the stopping-places on the route with a statement of the number of miles between each. The Itinerary begins in Mauretania, at Tingis, and then goes on to cover most, but not quite all, of the Empire in a somewhat random fashion (FIG. I). While six routes are given in Sardinia and one even in Corsica, there is none in Crete or Cyprus—in contrast to the Peutinger Table,3 which includes routes in Cyprus and Crete but not in Corsica and Sardinia. On the mainland the most obvious omission is that of transdanubian Dacia, but Achaea and Macedonia are also poorly represented and there are no routes at all in Lycia and Pamphylia. While Spain is treated generously, there are large gaps in Gaul, especially in Armorica; and even Spain is not dealt with as a province, or group of provinces, on its own, since some of its routes spill over into Gaul. A consideration of this and similar cases shows that the apparent coherence of the British section is largely fortuitous and derives from the fact that Britain is an island.