Disregarding other ancient sources, sometimes more precise in specific aspects, to represent the general road network in the Roman Empire, on this occasion we prefer to be guided by the famous painted map known as Tabula Peutingeriana. It was named after Konrad Peutinger, who was given it in 1507 by Conrad Celtes, who discovered it.
The map was made in the 12th or 13th century, and is the only copy remaining of the original document, a world map dating from the middle of the 4th century, according to some, and from the last third of the 2nd century, according to others. It is divided into 11 segments kept in the Vienna Imperial Library. Another for the western ends of the Empire (Britannia, Hispania and Mauritania Tingitana) is lost. In the early 20th century, Konrad Miller tried to reconstruct this, using another document in the same family, the Ravenna Cosmography. Originally, the tabula consisted of an undivided roll of parchment of length 6.882 m and width 34 cm. It was divided in 1863 to ensure its preservation.
Ravennatis Anonymi Cosmographia
The Ravenna Cosmography (Ravennatis Anonymi Cosmographia), also popularly known as the Ravennate, is a text compilation made by a Christian cosmographer in the 7th century from descriptions of Roman itineraries from previous centuries (the 3rd or 4th centuries). It is a valuable written source to keep in mind when studying Roman roads. However, it does not provide the distances between one mansio or another, limiting itself only to mentioning their names and the routes.
Certainly, there are other illustrated maps (tabulae pictae) relating to Roman times, but none with the rigour and extension of the present, a true itinerary of the Roman Empire and even the Persian Empire (which did not lack for cities); with feminine allegories for the 3 most important (Rome, Constantinople and Antioch) and architectural icons according to the category of each; also, the distances between them (in miles normally, but also in leagues in the case of Gaul, and parasangs in Persia) and geographical features, especially coasts, rivers and mountains.
The parasang (Persian: فرسنگ / فرسخ / پرسنگ) is a historical Iranian unit of distance comparable to the European league. The parasang may have originally been a fraction of the distance an infantryman could walk in a particular period of time. Herodotus speaks of an army travelling the equivalent of 5 parasangs in one day. Herodotus’ own definition of this estimates the distance at 5.3-5.7 km.
Many scholars have dealt with this imposing map of the Roman Empire. The edition we follow is from one of the first and most eminent, Konrad Miller, which is considered one of the most complete and precise of those preserved.