Beyond Athyra there is a place which the natives call Episcopia. The Emperor Justinian perceiving that this place lay exposed to the attacks of the enemy, more especially as there was no strong place, but the country was entirely unguarded, built a fort there, the towers of which he constructed, not in the usual manner, but as follows. From the ‘curtain’ wall projects a building, narrow at first, but very wide at the outer end, upon which each of the towers is built. It is not possible for an enemy to approach near to this wall, since they come between these towers, and are overwhelmed by the cross-fire which the garrison easily pour upon their heads. He placed the gates, not in the usual manner, between two towers, but obliquely in a small projection of the wall, so that they are not seen by the enemy, but are hidden behind the wall. This work was performed for the Emperor by Theodorus Silentiarius, a very clever man. Thus was this fort constructed. We must now proceed to make some mention of the ‘long walls.’ IX. The sea which proceeds from the ocean and Spain, with Europe on its left hand, flows in the same easterly direction as far as Thrace, but there divides into two portions, one of which proceeds towards the east, while another makes a short bend and terminates in the Euxine Sea. When it reaches Byzantium, it winds round the city on its eastern side, as though round a goal, and continues its course in a much more oblique direction, proceeding by a strait which turns the upper and lower parts of Thrace into an isthmus; not that the sea there is divided into two parts, as is the case in other isthmuses, but it circles round in a singular manner and embraces Thrace on both sides, and more especially the whole suburbs of Byzantium. These suburbs the inhabitants have built over and adorned, not merely for their use, but with an arrogant and boundless luxury, and with all the license which is produced by wealth. Here they have stored much furniture, and preserved many works of art. Whenever, therefore, the barbarians suddenly invade the Roman Empire, these places suffer far more damage than the rest, and are in fact utterly ruined. The Emperor Anastasius, wishing to prevent this, built long walls[79] at a place no less than forty miles from Byzantium, joining the two seas where they were distant two days’ journey from one another. Having constructed these works, he supposed that all within them had been made secure; they were, however, the cause of still greater disasters, for it was not possible either to build so enormous a work firmly, or to guard it with proper care; while when the enemy made themselves masters of one part of the long wall, they conquered the remainder of the garrison without difficulty, assailed the rest of the people unexpectedly, and did more mischief than can easily be described.