The Antonine Itinerary is a register of the stations and distances along the various roads of the Roman empire, containing directions how to get from one Roman settlement to another. According to the 1911 Encyclopædia Britannica, the Antonini Itinerarium is seemingly based on official documents, probably of the survey organized by Julius Caesar, and carried out under Augustus. Due to the scarcity of other extant sources of this information, it is a very valuable source. Nothing is known with certainty as to the date or author. It is considered probable that the date of the original edition was the beginning of the 3rd century, while that which we possess is to be assigned to the time of Diocletian. Although traditionally ascribed to the patronage of Antoninus Augustus, if the author or promoter of the work is one of the emperors, it is most likely to be Antoninus Caracalla