The lines connecting towns are intended only to facilitate comparison.
Both sections of Ptolemy’s map (12b) use a 4 by 1 graticule. On a modern scale map, the upper section would be magnified by one-third. It shows forts established only after Agricola’s advance into northern Caledonia in c. AD 83 and was probably acquired separately.
The distension of the map to the south-west suggests that the coordinates for Rerigonium belonged to the less accurate coastal data. Vindogara would be a site near Patna on the supposed Roman road from Ayr if the map is accurate; the bay called Vindogara would suggest Ayr itself.
