The Roman History · Amm. 24.4.10

And by this time the emperor was besieging with all his might and with a triple line of heavily armed soldiers this town which was fortified with a double wall; and he had great hope of succeeding in his enterprise. But if the attempt was indispensable, the execution was very difficult. For the approach to the town lay everywhere over rocks of great height and abruptness; across which there was no straight road; and dangers of two kinds seemed to render the place inaccessible. In the first place there were towers formidable both for their height and for the number of their garrison; equalling in height the natural mountain on which the citadel was built; and secondly, a sloping plain reached down to the river, which again was protected by stout ramparts.

Ammianus Marcellinus · translated by C. D. Yonge · 1911 reprint
C. D. Yonge translation (preface dated February 1862); G. Bell and Sons, 1911; Project Gutenberg #28587
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