IV. As one goes from the city of Dara towards the land of Persia, there lies on the left a tract entirely impassable for carriages or horses, extending to the distance of about two days’ journey for a lightly-equipped traveller, ending in an abrupt and precipitous place called Rhabdium.[38] The land on each side of this road to Rhabdium belongs for a great distance to Persia. When I first saw this I was surprised at it, and inquired of the people of the country how it was that a road and tract belonging to the Romans should have enemy’s land on each side of it. They answered, that this country once belonged to the Persians, but that at the request of the King of Persia one of the Roman Emperors gave a village abounding in vines near Martyropolis,[39] and received this region in exchange for it. The city of Rhabdium stands upon precipitous and wild rocks, which there rise to a wondrous height; below it is a region which they call ‘the field of the Romans,’ out of wonder, I suppose, at its belonging to the Romans, though it lies in the midst of the Persian country. This Roman field lies on flat ground, and is fruitful in all kinds of crops; one might conjecture this from the fact that the Persian frontier surrounds it on every side. There is a very celebrated fort in Persia, named Sisauranum, which the Emperor Justinian once captured and razed to the ground; taking prisoners a great number of Persian cavalry, together with their leader Bleschanes. This place lies at a distance of two days’ journey from Dara for a lightly-equipped traveller, and is about three miles distant from Rhabdium. It was formerly unguarded, and altogether neglected by the Romans, so that it never received from them any garrison, fortification, or any other benefit, wherefore the peasants who tilled this country, of which I just spoke, besides the ordinary taxes, paid an annual tribute of fifty gold pieces to the Persians, in order that they might possess their lands and enjoy the produce of them in security. All this was altered for them by the Emperor Justinian, who enclosed Rhabdium with fortifications, which he built upon the summit of the mountain which rises there, and, taking advantage of the position of the ground, rendered it impossible for the enemy to approach it. As those who dwelt in it were in want of water, there being no springs on the top of the cliff, he constructed two cisterns, and by digging into the rocks in many places made large reservoirs of water, so that the rain-water might collect, and the garrison might use it freely, and not be liable to capture through distress for want of water.