Demosios dromos

The cursus publicus (Latin: "the public way"; Ancient Greek: δημόσιος δρόμος, dēmósios drómos) was the state-run courier and transportation service of the Roman Empire, later inherited by the Byzantine Empire. The Emperor Augustus created it to transport messages, officials, and tax revenues between the provinces and Italy. The service was still fully functioning in the first half of the sixth century in the Byzantine Empire, when the historian Procopius accuses Emperor Justinian of dismantling most of its sections, except for the route leading to the Persian border. The extent of the cursus publicus is shown in the Tabula Peutingeriana, a map of the Roman road network dating from around AD 400.

A series of forts and stations were spread out along the major road systems connecting the regions of the Roman world. These relay points (stationes) provided horses to dispatch riders, usually soldiers, and vehicles for magistrates or officers of the court. The vehicles were called clabulae, but little is known of them. A diploma or certificate issued by the emperor himself was necessary to use the services supplied by the cursus publicus. Abuses of the system existed, for governors and minor appointees used the diplomata to give themselves and their families free transport. Forgeries and stolen diplomata were also used. Pliny and Trajan write about the necessity of those who wish to send things via the imperial post to keep up-to-date licenses.

Another term, perhaps more accurate if less common, for the cursus publicus is the cursus vehicularis, particularly in the period before the reforms of Diocletian. We know of at least one 'Praefectus Vehiculorum', Lucius Volusius Maecianus who held the office during the reign of Antoninus Pius. Presumably he had some sort of supervisory responsibility to ensure the effective operation of the network of stations throughout the Empire and to discourage abuse of the facility by those not entitled to use it. There is evidence that inspectors oversaw the functioning of the system in the provinces and it may be conjectured that they reported to the 'Praefectus' in Rome. However, the office does not seem to have been considered a full-time job because Maecianus was also the law tutor of the young Marcus Aurelius which seems to have been his main function.

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