OmnesViae is based on Richard Talbert's research work on the Tabula Peutingeriana. It is a digitally reconstructed map of Roman medieval routes across Europe from about the year 300 CE. The geolocations are mainly obtained from the Pleiades gazetteer. The author of this resource went on to create Omnesviae.org's successor, Vici.org mapping nearby Roman and Classical history.
Taken from website (accessed 2016-05-31):
I don't claim ownership of any underlying data, not even for the parts that are the fruit of my own research work. I kindly ask the creators of derived works to make the data behind those works also freely available. When using data or output from OmnesViae, please create a link or reference to this work. Please let me know when you use OmnesViae in your publications or derived works.